Dimensions of Physical Quantities

Hi friends, I hope you are all well. Today we can talk about the dimensions of all physical quantities which include the base quantities and the derived quantities. Dimensions of physical quantities are the fundamental part that helps us understand the physical and natural properties of any physical quantity. In modern science and technology, in engineering, and in different fields of physics where physical quantities units are used, the dimensions of these units help to derive a new formula and are also used in derivations. Dimensions of physical quantities also convey the detail of the types of physical quantity. 

Dimension of physical quantities also helps to check the correctness of the equation and the formula that we can derive or use to solve the problems. Dimension of the physical quantities systematically expressed the physical quantities units. For analysis of the formula and the physical quantities, we can also use the dimensions of these quantities. Now we can start our detailed discussion about the dimensions of physical quantities which include the base quantities dimensions, derived quantities dimensions, and the application and analysis of the physical quantities in physics.

What are physical quantities?

Definition:

   Physical quantities are defined as: 

                      “The quantities which can be measured and quantified by measurements are termed as physical quantities.” For example mass, length weight, electric current, and many other various quantities. These physical quantities can be expressed in the algebraic form and when measured we can use different units for their measurements. To know the correctness of these units we can use dimension analysis.

        For example for the quantity length we can use the unit meter and their symbol is m so by using the dimension of the meter we can verify them.

Types:

 There are two main types of physical quantities units which are given below:

  • Base quantities 

  • Derived quantities 

The units that can be used to describe these physical quantities are known as base quantity units and the derived quantity units.

Dimensions of physical quantities: 

Dimension of physical quantities is defined as: 

"The fundamental quantities which can be expressed in the form of raised power to describe the physical quantities are termed as dimensions of physical quantities."

The unit and the dimension of the physical quantity are written in the square brackets. For example, the unit of length is m and the symbol is m but their dimension is L.

The dimensions of base physical quantities and the derived physical quantities in detail are given below: 

Base physical dimensions and their units: 

There are seven basic base physical quantities units which are also known as the building blocks units from which other units are derived. The dimensions of these base physical quantities with their units and definitions in detail are given there:


Base quantity 

Symbol 

Unit 

SI unit symbol 

Description 

Dimension 

Length 

L

meter

m

The unit meter is used for the length and the length describes the distance between the two objects and also describes the height and the width of an object.

L

Mass 

m

kilogram

kg

The quantity mass is used to measure the amount of matter of the objects. The measurements that can be measured are expressed in the unit kilogram.

M

Time 

t

second

s

The physical quantity of time is used to measure the duration of the process and events like the duration of waves and oscillations. These measurements can be expressed with the unit second.

T

Electric current 

I

Ampere

A

The flow of the electric charge in the electric circuits can be measured by using the term electric current and this measurement is expressed with the unit ampere. 

I

Amount of substance 

N

mole

mol

To measure the number of atoms, molecules, and other entities in the compound or matter we can use the term amount of substance the unit which is used to express the amount of substance is mole.

N

Luminous intensity 

J

candela

cd

The power of light can be measured in terms of luminous intensity and these measurements are expressed with the unit candela.

J

Thermodynamic temperature

Ө

kelvin

k

The temperature in the form of heat which may be endothermic or exothermic released from the thermodynamic system is calculated or, measured and these measurements are expressed with the unit kelvin. 

Ө

Derived physical units with their dimensions: 

Derived units are derived from the seven basic base quantities units such as area, volume, power, and many others. Some of these derived units with their symbols and dimensions are given below:


Derived Quantities 

Symbols

Formula and relation with other quantities 

Dimensions 

Dimensions related to the formula

SI units 

SI units symbol

Force 

F

mass acceleration 

m= M

acceleration = LT-2

MLT-2

Newton 

N

Area 

A

length breadth 

L= L

breadth=L

M0L2T0

Meter square 

m2

Density 

ρ

mass volume

m= M

volume = L3

ML-3T0

Kilogram cubic per meter

kgm-3

stress

σ

Forcearea

F= MLT-2

A= L2

ML-1T-2

Newton per meter square 

Nm-2

Surface energy 

σs

energyarea

energy= ML2T-2

Area = L2

ML0T-2

Candela meter per second square 

Jm-2

Impulse 

J, imp

force time

force= MLT-2

Time= T

MLT-1

Newton per second 

Ns-1

Strain 

ε

change in dimensionorginal dimension

Dimensionless 

—-

—---

—---

Hubble constant 

H0

velocity of recession distance

velocity= LT-1

distance= L

M0L0T-1

Per second

s-1

Coefficient of elasticity 

δ

strssstrain

stress= ML-1T-2

strain=1 

ML-1T-2

Newton per meter square 

Nm-2

Volume 

V

Length height breadth 

length= L

height= L

breadth= L

M0L3T0

Cubic meter 

m3

Thrust 

N

Force 

force = MLT-2

MLT-2

Newton per meter square or Pascal 

Nm-2or Pa

Linear acceleration 

a

velocitytime

velocity= LT-1

time= T

M0LT-2

Meter per second square 

ms-2

Work 

W

Force distance

force= MLT-2

distance= L

ML2T-2

joule

J

Specific volume 

v

volume/mass 

volume= L3

mass= M

M-1L3T0

Cubic meter per kilogram

m3kg-1

Specific gravity 

s.g

density of material density of water

    —---

Dimenonless 



Tension 

T

Force 

force= MLT-2

MLT-2

Newton meter per square and Pascal 

Nm-2 or Pa

Surface tension 

Y

force/ length 

Force= ML0T-2

length = L

ML0T-2

Newton per meter 

Nm-1

Radius of gyration 

k

distance

distance= L

L

meter

m

Angular velocity 

ω

angle/ time 

angle= L

time= T

LT-1

Radian per second

rs-1

Momentum 

p

Mass velocity 

mass= M

velocity= LT-1

MLT-1

Kilogram meter per second

Kg ms-1

Rate flow

Q

volume/ time 

Volume =L3

Time= T

M0L3 T-1

Cubic meter per second 

m3s-1

Frequency 

λ

No vibrations/ time 

Time= T

M0L0T-1

meter

m

Heat 

Q

energy

energy= M1L2T-2

M1L2T-2

joule

J

Buoyant force


force

force= M1L1T-2

M1L1T-2

Newton 

N

Plancks constant 

h

energy/ frequency 

energy= M1L2

frequency= T

M1 L2T-1

Joule second 

Js



Dimensional analysis:

To derive the formula and the relationship between the different numerous physical quantities we can use a method or a technique known as dimensional analysis. Dimensional analysis can also be used to identify and determine the correctness of the equation and the formula and also change the units from one system to another systems. Dimensional analysis is based on the following points which are given there: 

  • Principles of dimensional analysis

  • Steps involved in the dimensional analysis 

Details of these points are given below: 

Principles of dimensional analysis: 

      Principles of dimensional analysis include:

  •  Derivation of formulas 

  • Dimensional homogeneity 

  • Conversion of units 

Conversions of units:  

We can convert the units with the help of dimensional analysis in some other units. But the units that can we convert are expressed in terms of the base units. Some examples of conversion of the units are given there:

  •  The unit square per meter which we we used to express the velocity is converted into some other base unit like km/h through dimension analysis.

  • If we can measure the distance in the units meters then we can convert it into the other base units like meters per hour.

 Dimensional homogeneity: 

The formula or the equation that we may derive and use for solving the problems has equal and the same similar dimensions on both sides which proves that the equation is correct. if the dimensions on both sides are not the same it proves that the equation is not correct. So dimension analysis also helps to identify or determine whether the equation or formula is correct or not. Some examples are given there:

  • For example, the formula or area is A = Length breadth. The dimension of the area is L2 and on the other side, the dimension of length is L and breadth dimension is L so on both sides dimensions are the same proves that the formula is correct.

  • Another example is a force equal to F= ma and the dimension of force is MLT-2 and on the other side the dimension of m is M and the dimension of a is LT-2. so it proves that the formula is correct because the dimensions on both sides are the same.

Derivation of formulas:

  We can derive the different authentic formulas by using numerous physical quantities with the help of dimensional analysis. Dimensional analysis helps to understand the property of quantity which we can use to derive the formula. Some examples are given there: 

  • We can derive the period of the pendulum by using the dimension of time and distance.

  • We can also derive the formula for the force by using different physical quantities like mass, acceleration, and time and we can also check whether the equation is correct or not with the help of dimensional analysis.


Steps which are involved in the dimensional analysis:

The steps which are involved in the dimensional analysis are given there:

  • Set up the equation 

  • Identify the base quantity 

  • Write the dimensional formula 

  • Solve for the unknowns 

Set up the equation: 

  For dimensional analysis, it is essential to check or confirm that the equation or formula we are using has the same dimensions on both sides and they are equal to each other. Some examples are given below: 

  •   The formula which is used for work is W= force distance the dimension for work is the same and equal to the dimension of force and the distance. 

  • Another example is the formula of force is F= ma and the dimension of force is equal to the dimension of mass and acceleration so that's why the dimension analysis helps to identify the equation is correct. 


Identify the base quantities: 

In dimensional analysis, it is essential to identify the physical quantities that we are using to derive the formula or to solve the problems. Some examples are given below: 

  • Identify the mass, length, volume, and other physical quantities and then use their dimension for dimensional analysis.

Solve for the unknowns: 

              To identify the unknown physical quantities we can use the dimensions. And by the help of dimensions we can identify and determine the right physical quantity. Some examples are given below: 

  • We can identify the gravitational constant G by using the dimensions and also determine their dimensions with the help of dimensional analysis.

  • For another example, we can determine the pendulum period by using the different dimensional equations, and after determining we can also identify their dimension with the help of dimensional analysis.

Write the dimensional formula: 

In the formula that we derived or used to solve the problems, it is essential to write the dimension of all quantities that can be used in the formula. Some examples are given below:

  • The dimensional formula of the area is L2.

  • The dimensional formula of power is Ml2T-3.

Applications of dimensional analysis:

In the era of modern sciences and technology, engineers and other scientists measure complex quantities. Dimensional analysis helps to measure these complex quantities and also helps to derive new complex formulas and check the correctness of the derived formula by using the dimensions. Now in the modern era of physics and engineering, dimensional analysis can be used in many different fields. Some applications of dimensional analysis are given below: 

  • Biophysics

  • Relativity 

  • Plancks constant

  • Engineering 

Biophysics:

In biophysics, we can study and understand how the substance in the body or biological tissues can be moved or flow. Because diffusion mechanism can be used and we can measure and express them in some units so that's why we can use dimension analysis in it also 

Some examples are given below:

  • The coefficient of diffusion can be described as the flow of material from one to another place and its dimensional formula is L2T-1.


Relativity:

To understand the relationship between mass and energy we can use the dimensional analysis method. Because they help to determine or identify the quantities that can be used in their dimensions. some examples are given there: 

  • The formula which can be derived by Einstein is based on the relationship between the mass and the speed of light the formula is F=mc2 and the dimensions of m is M and the dimension of c2 is LT-1.

Quantum mechanics:

In quantum mechanics, we can understand the energy levels in the atoms and with the help of dimensional analysis, we can check the correctness of equations and detail understand the the energy levels in the atoms. Examples of dimensional analysis in quantum mechanics are given there:

  • For dimensional analysis and understanding the energy level we can use the formula of Plancks constant which is E=hv in this h is for energy level v is for frequency and their dimension is ML2T-1.

Engineering:

In engineering dimensional analysis is used for stress and strain because they can design the new materials and check their capacity to bear the load. So that's why dimensional analysis is used to determine the dimensions of stress and strain. Their example is given there: 

  • In engineering, the stress on the object at force per unit area and strain changes the length and their dimensional analysis ML-1T-2.

Conclusion:

Dimensional analysis plays a vital role in the modern era of science and modern technology because in this era we can measure complex physical quantities and checking the correctness of dimensional analysis is essential. It can also help to derive the new formula and understand the natural properties of the quantities. By using dimensional analysis scientists and engineers can achieve highly precise and accurate measurements of complex physical quantities. 

With time when the physical quantities become more complex and developed then the dimensional analysis techniques can also be developed and adopt different changes in them.  The steps that can included in the dimensional analysis can be developed and more steps are included for the analysis of complex physical quantities which helps the scientist to understand the quantities and give the most precise and accurate result according to complexity.

Total Uncertainty in the Measurements

Hi friends, I hope you are all well. In this article, we can discuss the uncertainty in the measurements which can be measured. In the era of modern science and technology or modern physics, scientists can measure complex quantities and these measurements are not precise and accurate somehow doubt is present in these measurements, these doubts are suspicious known as uncertainty in the measurements. In physics or other fields of technology and engineering measurement is essential to measure or understand the quantity of a material or an object. Because every measurement is correct there are always some doubts or doubtful digits and they are called uncertainty in the measurements.

Now in this article, we can explore the history, definition, quantifying methods, and different techniques that can be used to minimize uncertainty and also explore their applications and significance in different fields of engineering and physics.

History:

All substantial National measurement institutes can research the uncertainty in the measurements and give detailed documents about the measurement which is known as GUM and stands for the “Guide of Uncertainty in the Measurements.” this document gives the details about the uncertainties in the measurements. In metrology measurements when we can take measurements of the object many times it is confirmed that somehow measurements are not correct and precise. Or the doubtful measurements are termed uncertainty. All the measurements are not always correct because the measurement results depend upon the instrument's efficiency and the skilled person who can take measurements That is why uncertainty comes into measurements due to many various factors that may depend upon the environmental factors also.

Measurements are essential to determine the quantity of the physical quantity or any objects. Measurements also play a vital role at the economic level. The quality of laboratories can also determined by their calibration results because the exact measurements help to understand the quantity of the object. So that's why the ASME which stands for the American Society of Mechanical Engineers can present different standards for the uncertainty in the measurements. According to their standards, the measurements are done and engineers and scientists in laboratories can also measure the quality of different measurements. 

What is the uncertainty in the measurements: 

Definition: 

Uncertainty in the measurements is defined as:

"The measurement which can we measured have lack of certainty and they have a great difference between the true value and the measurement value which be measured."

In simple words, the measurements we can measure have some doubts and their results do not according to the expectations and lack sureness are termed as uncertainty in the measurements. Uncertainty in the measurements is common because not every measurement is accurate or precise. For instance, we can measure the length which is about 6.7cm with a meter ruler but the true value range is about 6.62 or 6.75cm so the uncertainty in this measurement is approximately 0.05cm. Another example is if we measure the height of an object and the measurement which we can measure is 5.5m but the true value range is 5.3m or 5.7m so in this measurement the uncertainty is approximately equal to 0.02m.

Types of uncertainty in the measurements:

There are two major types of uncertainty in measurements which are given below: 

  • Type A uncertainty 

  • Type B uncertainty 

Type A uncertainty in measurements:

Type A uncertainty is defined as:

"The uncertainty measurement which can be evaluated through the different methods of statical analysis are known as type A uncertainty measurements."

 Generally, in type A uncertainty measurements we can measure or collect different data about the measurement and then observe the series of collected data, and then evaluate the uncertainty which are present in these measurements.

For example, we can take measurements of an object many times or maybe 20 times and then evaluate and observe the results of these measurements and then analyze the uncertainty in these measurements. from empirical data, we can directly identify or determine the type A uncertainty in the measurements. Another example is when we want precise and accurate measurements then we can measure the same measurements many times like if we can measure the length and the measurements range between 5.7cm to 14cm and in between different measurements occur after these measurements we can observe or estimate the average uncertainty.

Type A uncertainty evaluating methods:

Type A uncertainty can be measured by repeated measurements of the measuring object and evaluated through statistical methods or techniques. Some statistical methods that are included in the evaluation of type A uncertainty are given below: 

  • Confidence intervals

  • Arithmetic means

  • Standard error of the mean

  • Degree of freedom 

  • Standard deviation 

Confidence intervals:

Confidence interval is defined as:

"The true and standard values that can be measured through the measurement of quantity, and confidence interval convey the range of accuracy with a confidence level of the true measured value."

Formula: 

This formula can be used for a normal distribution which has a 95% confidence interval. The formula is given there:

                                         μ z SEM 

                                         μ z SEM 

There,

             z  is for the confidence level which can we desire and it is approximately equal to 1.96 for the normal distribution with a confidence level of 95%

Arithmetic mean: 

           Arithmetic means is defined as: 

                                      “The set of measured numbers, the all measured numbers are added and dived by the total numbers which are present in the set and the central number which is present in the set also added with the all measured numbers”.

To know an average of all measured measurements we can use the arithmetic formula because, through this statistical technique, we can evaluate the type A uncertainty in the measured sets. 

Formula: 

The formula which is used to calculate the average of the measured set is given there: 

                             x = 1n i=1nxi

Standard error of the mean: 

The standard error of the mean is defined as: 

                                   “ the uncertainty which is present in the average that can be calculated from the set of measurements with no of measurements and the standard deviation, these estimate can be conveyed by the standard error of the mean.”


Formula: 

 The formulas that are used for calculating the standard error of the mean are given there:

                                  SEM= σN

there, 

SEM = standard error of the mean

σ= standard deviation

N = no of measurements

Standard deviation:

Standard deviation can be defined as: 

                             “The average can be measured from the dispersion of the set of collected measurements.”

            Standard deviation can be used to measure the average variance which can be essential for evaluating the Type A uncertainty.

Formula:

    The formula that can be used for the standard deviation or measure the average variances is given  there: 

                       σ= 1n-1i=1n(xi-x)2

Degree of freedom:

The degree of freedom can be defined as:

               After the calculation of the standard deviation and the average the final numbers can be calculated freely for statistical analysis and the final values can help to understand the type A uncertainty and the degree of freedom.

Formula: 

       The formula that is used for the degree of freedom is given there:

                           v= n - 1

Sources of Type A uncertainty in the measurements: 

The main causes and sources of the Type A uncertainty in the measurements are given there:

  • Environmental changes

  • Human factors 

  • Instrumental fluctuations

Methods used to reduce type A uncertainty:

The methods that can reduce the uncertainty in the measurements are given below:

  • Advanced measurement techniques

  • Repeated numbers of measurements

  • Control environmental factors

  • Improving measurements techniques

 

Type B uncertainty in the measurements: 

Type b uncertainty can be defined as: 

"the uncertainty which can be evaluated by using different methods except the statistical analysis of measurements. Type B uncertainty can't be evaluated through statistical analysis they can be evaluated through calibration certificates, scientists' judgment, and through the publishers."

Type B uncertainty can be measured differently from Type A uncertainty in the measurements because it is mostly evaluated through the collected information and through the publishers. This type of error is also common the main sources and the causes of these uncertainties can be explained below.

Type B uncertainty measurement evaluating methods: 

The methods that can be used to evaluate the type B uncertainties in the measurements are given below:

  • Expert judgment 

  • Manufacturer specification 

  • Theoretical analysis 

  • Reviews of calibration certificates 

  • Reference material data

  • Chats of collected data information

Expert judgment: 

When we can do measurements but do have not direct measurements and data then the uncertainty measurement is provided to the experts who have experienced and understand the limitations and uncertainties of the measurements. Then the judges understand the uncertainty and then identify the type of uncertainty and try to reduce these uncertainties. Some examples are given below:

  • The scientists who can do experiments and want to change into theory the council and the judges understand the experiment according to their experience and then allow them.

  • A well-experienced scientist or metrologist can measure the uncertainty in the measurements through their experience and knowledge.

Calibration certificates:

         The type B uncertainty can be evaluated by using the calibration certificate because the calibration certificates convey information and details about the accuracy and precision of the measuring instruments. Calibration certificates also provide information about the correction of uncertainty in the measurements. 

Example: 

The uncertainty of the voltmeter is 0.05 provided in the calibration certificate and how to recover this uncertainty information is also present in it.

Reference material data:

The uncertain information and documents are provided through the reference material data. The information and values that are provided through these reference data help to improve the uncertainty in the measurements that can be calculated.

Example:

            The certified uncertainty of the gas analyzer is approximately about 0.1% and the reference data is provided to minimize the uncertainty in the measurements.

Manufactures specification:

The instrument's specification accuracy, precision, and limits can only defined by the manufacturers because they understand the nature of their instruments and they also determine or estimate the uncertainty that can produced by their instrument during the measurements.

Example: 

For the dimensional measurements the instruments we can use a digital micrometer and their accuracy is about 0.002 it can also budget the uncertainty measurement in it.

Theoretical analysis: 

There are different theoretical models are present that can convey detailed information about the uncertainties in the measurements. Because these models are based on the assumptions and the practical experiences. By using these models we can also estimate and identify the uncertainties in the measurements which can be measured.

Example: 

We can estimate the uncertainty and the precision in the vacuum of the speed of light and we can measure these uncertainties that are based on precision and we can calculate them.

Sources which can cause type B uncertainty: 

The sources which can use the uncertainty in the measurements are given below: 

  • Environmental conditions

  • Previous measurements

  • Manufactures specification

  • Theoretical models 

  • Instrumental calibration

  • Previous measurements  

The combining component of Type B uncertainty: 

In the combination of different type b components, we can use the root sum square method to estimate and calculate the uncertainty in the measurements. The all components that are combined are independent but we can combine them to estimate the uncertainty in the measurements precisely. 

Formula:

               uc(y) = i=1nciu(xi)2

Methods to minimize the type B uncertainty: 

We can reduce the type B uncertainty in the measurements if we can follow these given steps. Because it can help to reduce tp understanding of the uncertainties in the measurements. The methods and the steps are given below: 

  • Used advanced measurement techniques 

  • Improved calibration

  • Used high-quality reference data 

  • Enhanced environmental controls.

Sources of uncertainty in the measurements:

Generally, uncertainty in the measurements occurs due to many sources but the major two are 

  • Random error

  • Systematic error 

The sources and details of these errors are given below: 

Random error: 

Random errors are common because they can caused by many different sources and they may be reduced by doing repeated measurements and by estimating the main cause of error. Some major sources which can cause this error are given there:

  • Observer variability

  • Environmental noise

  • Instrumental fluctuations

Systematic error: 

              This error occurs due to the imperfect instruments usage and the unskilled persons who can take measurements but the main sources and causes of systematic error are given there: 

  • Methodological error

  • Instrumental error

  • Observer error

  • Environmental factors 

Techniques and methods to reduce uncertainty: 

The techniques and some methods that are used to reduce the uncertainty are given there: 

  • Replicates and repeat measurements 

  • Randomization

  • Calibration and standardization

  • Improved experimental designs

  • Control variables

Advanced measurement techniques: 

To reduce the uncertainty in the measurements we can use many different advanced techniques some are given there: 

  • Error-correcting algorithm

  • Automated data collection

  • High precision instruments

  • Skilled persons 

In scientific research the significance of uncertainty: 

                 In scientific research the measurement of uncertainty is essential and it is also essential to reduce it because the scientists try to make precise and accurate measurements according to the calibration certificates, the significance of uncertainty in scientific research is given there: 

  •  Reproducibility

  • Peer review

  • Validation

  • Transparent reporting 

Application of uncertainty in the management: 

In the field of modern technology and engineering, in measurements uncertainty and error are common but by using different techniques we can reduce them. Some applications of uncertainty in the management are given there:

  • Medical and biological research

  • Pollution monitoring

  • Quality control

  • Climate modeling

  • Safety standards

  • Drug efficacy

  • Diagnostic accuracy

Conclusion: 

The uncertainty in the measurements is common but in modern science and technology or different fields of science and physics, we can reduce the uncertainty in the measurements using many different techniques because scientists and engineers want to measure the precise and accurate measured values. Because the experts can agree on the measurements which are according to the standard values of the calibration certificates. Because the national measuring institutes and the American Society of Measurements can present the standard suits for measurements that are used to reduce or estimate the uncertainty in the measurements.

Precision and Accuracy in Physics

Hello friends, I hope you are all doing well. In this article, we can talk about the precision and accuracy of the measurement. Both of these are used to analyze errors in the measurements which can be calculated. In the era of science and modern technology, accuracy and precision are essential to depict the quality of the measurements. To measure the error in the measurement precision and accuracy techniques can be used because both are used for comprehensive measurement analysis.

To calculate or describe the random errors precision of measurement can be used but if we want to describe the systematic error, accuracy of measurements can be used. Now the details of precision and accuracy, their definition, differences, examples, and their application in different fields are given below:

Difference between precision  and accuracy:

The main differences between precision and accuracy are given below:


Precision Accuracy

Definition: 

                   The reproducibility which can be measured in the measurement is known as precision.

On the other hand, precision can also be defined as the set of repeatability measurements and all measurements are close to each other but we precise the closest value. Because highly precise measurements can convey the best and very similar results.


Definition:

        The value that we can measure is close to the true value of the measurement is known as accuracy. 

Another definition of accuracy is that the value that can be measured is approximately equal or close to the accepted and the true value of the measured object.  Because accuracy provides the correct measurement of the object which can we measured. If the measurement that we can calculate is close to the standard value of measurement then it can be an accurate measured value. 


Accurate: 

             The measurements that can be calculated are precise but they can't be accurate because high precision can cause low accuracy.

Precision:

           The measurements that we can calculate are accurate but they are not precise because high accuracy affects the precision and causes low precision measurement.

     

Determined:

                To determine the precision we can calculate the object measurement many times and from a set of measured measurements we can determine the precise measurement value.

Determined: 

       Accuracy can be determined from a single measurement of an object which can be measured.

Random error: 

                  Random error can affect the precise measurement which we can determine.

Systematic error:

             The accuracy of the measurement can be affected by systematic error.

Accurate: 

           The measurements that we can measure are precise but not correct every time.

Precision: 

           The measurements that can be measured are accurate but these measurements are not correct anyway.


Reproducibility: 

            Precision can give a degree of reproducibility.

Conformity: 

         Accuracy provides the degree of conformity of measurements.

Relationship between the accuracy and precision:

The terms precision and accuracy are different from each other, but somehow they are related to each other. Because when we measure the object or any quantity measurement then it may be accurate but not to be precise but if we determine the periscred measurement then it not to be accurate so that why both terms are not present in the measurements at the same time.to understand the relation and the difference between the accuracy and measurement  and to improve the measurement techniques some common points are given there:

  • Low precision and  high accuracy
  • Low precision and  low accuracy
  • High precision and high accuracy
  • High precision and low accuracy

Low precision and high accuracy: 

When the measurements that we can calculate are close to the standard or true value but the measured values are not similar to each other then they have high accuracy but low precision because the measurements are not matched to each other. Some examples are given below:

  • The measurement of the field which we can calculate is 80 cm, 99.90 cm, and 100.02cm but the true or standard value is 100.10 cm so the values are accurate but they can’t be precise.

  • If we can calculate the length of an object and the measured value is 70.01m, 80.67m, and 90.01m, the true value is 80.67 then the all values are not precise but they are accurate. 

Low precision and low accuracy: 

The measured values that can be calculated through measurements are not close to the true value and also the set of measurements are not close to each other all the measurement values are different which means they have low precision and low accuracy. Some examples are given below: 

  • The measurements of the yields are 75.00 cm, 100.00 cm, and 112.00cm but the true value is 120.00cm. These values are not close to each other and neither one value is close to the true value so that is why they have low accuracy and low precision.

  • For instance, if the measurement is 95.00 cm, 106.00 cm, and 101.00cm but the true value is 105.07cm then they have both low accuracy and low precision.

High precision and high accuracy:

If the measured values that we can measure are close to the true and the standard value and the set of measurements that we can calculate are close to each other then we can say that the measurements which we can be calculated have high accuracy and also have high precision. Some examples of highly accurate and highly precise measurements are given below: 

  • The measurement of the length of the cylinder is 101m, 102m, and 103m and the true or standard value or accuracy is 102m then these values are precise and close to each other and they are also accurate because the measurement is close to the true value.

  • The measurement of the yield is 80cm, 82cm, 83cm, and 85cm or the true value is 83cm then they have high accuracy and high precision because the values are close to the true value and all sets of measurements are close to each other.

High precision and low accuracy: 

The measured measurements are similar or close to each other but these measurements are not close to the true or standard value. some examples of these measurements which have high precision but low accuracy are given below:

  • Measurement which we can measure is 79.01, 79.02, 79.03, and 79.08 but the true value is 89.01 That is why the measured values are close to each other but they are not close to the true value so it means they have high precision but low accuracy.
  • Another example is if we have measurements 56.8, 56.9, or 60 but the true value is 65.01 these measurements are close to each other but aren't close to the true value so these measurements have high precision but low accuracy.

Quantifying accuracy and precision:

The quantifying of accuracy and precision in detail are given below: 

Accuracy:

By using the numerous different statistical measures we can quantify the accuracy. The steps which are involved in quantifying the accuracy are given there:

  • Root mean squared error

  • Absolute error

  • Mean absolute error

  • Relative error

Their details are given there:

Root mean squared error(RMSE):

When we take the square roots of the average squared errors then it is known as root mean squared error. The formulas which are used for root mean squared error are given below:

                RMSE= 1ni=1n(measured valuei-true values)2

Absolute error:

Absolute errors are used to determine the difference between the true value and the measured value. The formulas which are used to determine the absolute error are given below:

                         Absolute error= measured value- true value

Mean absolute error(MAE):

In the set of measurements to calculate the average error in all the measurements mean absolute error formulas are used. The mean absolute error formula is given there: 

      MAE= 1ni=1nmeasured value- true value

Relative error:

To express the true value percentage with the absolute error we can use the relative error formula. The relative error formula is given there:

          Relative error= (absolute errortrue value) 100

Precision: 

By using the measure of variability we can quantify the precision. the steps which are included in the measure of variability are given there:

  • Coefficient of variation (CV)

  • Range 

  • Variance 

  • Standard deviation

Details of these points are given below:

Range:

Range is used to measure the difference between the maximum and the minimum values in the set of measured measurement values. The formula which can be used to measure the range is given below:

Range= Maximum value- minimum value

Standard deviation: 

By using the mean values from the set of measurements to can measure the dispersion of the measurement set. The formulas which are used in standard deviation are given below:

Standard deviation: 1n-1i=1n(measured value-mean value)2

Variance:

The square root of standard deviation is termed variance. The formula of variance is given there:

Variance= 1n-1i=1n (mmeasured value- mean value)2

Coefficient of variation: 

To express the ratio of the standard deviation we can use the formula of coefficient of variation. The formula for the coefficient of variation is given there:

Coefficient of variation: standard deviationmean value 100

Classification of accuracy and precision:

The classification of the accuracy and the precision are given below: 

Binary classification: 

To measure the statistical measurements we can use accuracy and we can use accuracy in the binary classification to determine or identify the conditions of measurements. By using the accuracy to can determine the exact ratio of the true positive or the true negative.

Types of error that affect the precision and accuracy: 

The two main types of errors that affect the precision and accuracy but these two types of error have also types two main types of errors are given below: 

  • Systematic error

  • Random error 

Details of these errors with their types are given there:

Systematic error: 

Systematic error is defined as an error that occurs many times due to faulty equipment or may be due to an unskilled person's measurement techniques and many other reasons. But this type of error can directly affect the measurement which can be measured and give the inefficient or bad results of the measurements. 

The sources that can cause the systematic error are given below:

  • Observational errors

  • Environmental errors 

  • Theoretical errors

  • Instrumental errors 

Observational errors:

Observational errors occur due to human mistakes. When they can read the reading and observe the reading efficiently then observational errors occur some examples are given below:

  •  The reading that can be measured by a human is approximately 3.4cm but it can't observe the certainty and uncertainty within it and also can’t read the exact digits of the reading.

  • When the unskilled person tries to observe the readings of very small quantities then the observational error occurs maximum because to measure the small quantities skilled person is used to observe the readings.

Environmental errors:

The error occurs due to environmental factors like temperature, humidity, and the fluctuation in the electromagnetic interference and also due to the airflow which can move instruments during the measurements. Some examples of environmental errors are given below:

  • When we use the thermometer to measure the temperature changing continuously in temperature can cause errors in the measurements.

  • To measure the current when we used the galvanometer the needle of the galvanometer moved again and again due to the magnetic field these fluctuations can cause errors in the measurements. 

Instrumental errors:

The error occurs due to the usage of imperfect or faulty instruments during measurements.

To measure the measurements without error firstly perfect instruments are essential because without this the measurement can't be correct when we measure anything. Some examples of instrumental errors are given below:

  • To measure the length of an object a ruler can be used but the readings on the ruler are visible clearly because it can be helped to measure the exact length.

  • A weight machine can be shown the weight of 2kg even if we can't put any object on it this is the instrumental error.

Theoretical error: 

Theoretical errors occur when we assume the theory model but nothing can happen in reality according to these models. Theoretical misassumptions can cause different errors in the measurement and provide the un accurate or precise results. Some examples of theoretical errors are given there:

  • During physics quantities measurements the air resistance is considered negligible.

Random errors: 

These errors occur due to various small unpredictable variables and these errors can’t be controlled because they occur in all measurements due to many different small or uncontrolled able variables. Some sources which can cause the random errors are given below: 

  • Environmental variability

  • Instrumental vartibility

  • observer variability

  • Sample variability

Environmental variability:

The fluctuations that can be occurred in the environment at any time like fluctuations in the temperature. Some examples are given there:

  • The flow of air can distract the measuring instrument from its place and cause errors in the reading

  • Air currents can also cause errors in the measurements.

Instrumental varaitabity:

The changing that occurs in the instrument during the reading there are many different instruments present that can use the noise or changes in it during measurements. Some examples are given below:

  • During measuring the current the galvanometer changing the needle again and again can cause errors in the readings or measurements.

Observer variability:

When the numerous observer measured the measurement at the same time their readings were different from each other due to sight issues and many other issues. Some examples are given below:

  • When the numerous observed reading through the stopwatch and stopwatch couldn't stop at the same time slime gave them vision issues.

Sample variability:

When we can measure the same object but the different samples have changes naturally we can measure them. These natural changes can also cause errors in the measurements. Some examples are given below:

  • When taking different samples of the same thing or object naturally their width or thickness can be changed then different measurements come with errors.

Improving accuracy and precision:

The accuracy and the precision can be improved if we can follow the following steps which are given there:

  • For improving accuracy:

  • Environmental control

  • Calibration

  • Instrument maintenance 

  • standardization

  • For improving precision:

  • Training

  • Environmental control

  • Reptation

  • Instrument quality

Application of precision and accuracy:

Application of precision and accuracy in different fields are given below:

  • Scientific research

  • In modern technology and sciences

  • In measurements

  • Healthcare fields

  • Monitoring environment 

  • In mathematics calculations.

Conclusion:

Precision and accuracy both play vital roles in measurements because in modern physics scientists can measure very small quantities and these quantities of measurement can be accurate without error due to the accuracy and precision. Both terms are the fundamental p[art of measurement in the analysis of comprehensive measurement. 

Precise and accurate measurements provide the quality of the measurements because without these terms in measurements, too many errors occur and they are not precise and accurate.

Technological Trends Transforming Security Equipment in 2024

It’s no secret that the tendrils of tech are tightly wrapped around the security equipment sector, and that’s good news for people and organizations with assets to protect. What you can’t afford to do is remain out of the loop on the developments that are impacting the market at the moment, so stick around and we’ll fill you in on the details that matter in 2024.

Integrating IoT with Security Systems

The combination of IoT with security systems is continuing to gain momentum this year. The idea is that interconnected devices can create smarter, more responsive security environments that are less reliant on manual monitoring. In this context it should be no surprise to find a whole host of network-enabled hardware when you explore security devices available today.

There are perks and pitfalls to IoT’s increased hold over security, so here’s a look at these so you can make an informed procurement decision:

Benefits

  • Real-Time Monitoring: IoT sensors enable continuous surveillance, providing real-time alerts for unauthorized access or anomalies. With 25% of businesses suffering at least $1,500 in losses to theft each month of the last year, it’s clear action is needed here.

  • Enhanced Automation: Automated locks, lights, and alarms respond instantly to detected threats, boosting efficiency.

  • Remote Access: Manage security systems from anywhere using mobile apps, which is perfect for frequent travelers or remote site managers.

  • Data Analytics: Collect detailed data on usage patterns and potential vulnerabilities, which improves predictive maintenance.

Challenges

  • Cybersecurity Risks: Interconnected devices can be vulnerable to hacking, and there was a 400% increase in IoT malware over the course of 2023. This means ensuring adequate encryption and secure protocols is crucial.

  • Interoperability Issues: Different brands and standards can cause compatibility problems, which makes selecting compatible hardware/software a must.

  • Complexity in Setup/Management: Installing an integrated system requires expertise, and professional installation often necessary.

Implementation Example

Let’s say you run a commercial warehouse. Integrated IoT allows it to monitor inventory levels while simultaneously tracking foot traffic through connected cameras. This dual function not only tightens security but also optimizes operations by predicting stock shortages based on entry patterns.

Image Source: Microsoft Designer

Taking Advantage of AI-Powered Surveillance

Surveillance systems imbued with artificial intelligence (AI) are in the process of redefining how we monitor and secure spaces, in addition to its influence over data security . These systems use advanced algorithms to provide smarter, more precise monitoring. Here’s a look at the ins and outs of what to expect from this tech:

Key Features

  • Object Recognition: AI can distinguish between people, animals, and objects, which reduces false alarms.

  • Behavior Analysis: Monitors and identifies suspicious activities based on movement patterns, and thus enhances threat detection.

  • Facial Recognition: Identifies individuals from databases quickly, which in turn streamlines access control.

Benefits

  • Improved Accuracy: Drastically cuts down on human error in surveillance by automating routine tasks.

  • 24/7 Vigilance: Never sleeps or gets tired, and instead constantly watches over premises without gaps in coverage.

  • Scalable Solutions: Easily scalable for different environments, from small businesses and even domestic premises to large campuses.

Challenges

  • Privacy Concerns: Potential misuse of facial recognition data raises ethical issues, so balancing security with privacy is essential. Indeed a KPMG report found that 53% of people see AI as introducing privacy problems, meaning there’s lots of awareness around this aspect.

  • High Costs: Advanced AI systems require significant investment in both hardware and software initially. Even if you outsource this to a third party vendor, the price of being an early adopter will not be cheap.

  • Data Management Complexity: Handling vast amounts of video data relies on robust storage solutions and processing power.

Implementation Example

If you’re responsible for security at a retail store, you could use an AI-powered system that not only spots shoplifting attempts but also tracks customer flow. The twofold benefits of loss prevention and gleaning insights into peak shopping times means that optimizing staff allocation is a much less complex affair.

Image Source: Microsoft Designer

Reveling in the Rise of Advanced Biometric Authentication

Biometric authentication has been part of the security sector for some time, but it’s only in 2024 that we are seeing the true extent of what the latest developments in this field can offer. Basically, it's not just about fingerprints anymore, as today we're dealing with multi-modal biometrics, combining several types of identifiers. Let’s unpack this in more detail:

Types of Biometrics

  • Facial Recognition: Scans and verifies facial features, and is enhanced with AI, as mentioned.

  • Iris Scanning: Uses unique patterns in the eye for identification.

  • Voice Recognition: Analyzes vocal characteristics.

  • Behavioral Biometrics: Monitors keystroke dynamics, mouse movements and other identifying behaviors for cybersecurity purposes.

Benefits

  • High Security: Difficult to replicate, as it adds a robust layer of protection over traditional methods like passwords or PINs.

  • Convenience: Faster access with fewer errors, since users don’t need to remember complex passwords.

  • Scalability: Easily integrates into various environments, from smartphones to secure business facilities.

Challenges

  • Privacy Concerns: Collection and storage of biometric data can be intrusive, so organizations must ensure proper safeguards are in place.

  • False Positives/Negatives: Environmental factors or physical changes can affect accuracy; continuous updates and calibrations needed.

  • Costly Implementation: Setting up advanced systems requires substantial investment initially.

Implementation Example

Consider the case of a high-security government building. Using multi-modal biometrics, an employee's identity gets verified through both iris scanning at the entrance and voice recognition at internal checkpoints. This layered approach ensures only authorized personnel gain access while maintaining a seamless user experience.

Image Source: Microsoft Designer

The Bottom Line

From a practical, commercial perspective it makes sense for businesses to prioritize the adoption of security equipment that intertwined elements of IoT, AI and advanced biometrics. This is a way of keeping physical and digital assets protected, while also ensuring the safety of employees and customers in 2024.

For homeowners, it is not as vital to ramp up security spending at the moment. That said, if you are thinking of installing equipment or upgrading an existing setup, looking for connected devices that are also AI-enabled makes sense. Biometrics is less relevant here but could bring convenience to the table if you want to move on from the traditional lock-and-key approach to access.

Significant Figures - Definition, Rules, Examples & Problems

Hi everyone, I hope you are doing well. Today in this post we can discuss significant figures. Significant figures can be evolved and traced a few hundred years ago and they can be developed from time to time according to the precise calculations that can be done in mathematics and modern science and technology.

The origin of significant figures can be traced to ancient times in Greece, Egypt, or many other countries where they can be used as Significant figures in calculations or mathematics. With time these significant figures can be used by astronomers, mathematicians, and scientists as well. To measure accurate and precise measurements they can use significant figures with scientific notation. In modern physics and mathematics, significant figures can be used essentially.

Now we can start our detailed discussion about significant figures and their definition, rules, examples, and problems in detail.

What are significant figures?

Details of significant figures are given below:

Definition: 

Significant figures can be defined as:

"In the number or calculated value the specific digits which provide precision and accuracy and also impart and convey the necessity of digits in the calculated measurement."

Significant figures include the zero or the nonzero digits. Significant figures are also known as significant digits and sig figs. When we make measurements or calculate the measurement such as when we measure length, pressure, and volume and the measured value is large then we can use significant or scientific notation method. or the most capable digits are estimated and called significant figures. 

Such as if we measure the volume of a cylinder and the measurement is approximately equal to 3.97L and the uncertainty is approximately equals to 0.04L. The actual volume of this cylinder is approximately between 3.93L and 1.01L, but we can't know the certain digits in this measurement completely. But all of these three figures are called significant figures.

Additionally, the value 345.0 has only 3 significant figures 3,4, and 5 the o digit is not termed as a significant figure because it is only a placeholder.

Types of digits: 

Some digits are not to be considered as a significant figure. So the types of digits that can't be considered significant figures are given below:

  • Spurious

  • Leading zero 

  • Trailing zero 

Trailing Zero:

The zero can only be present in the value or measurement as a placeholder. For example 1800 the last two zeros were only a placeholder but we can write the scientific notation we can raise the power of ten but in significant value, we only estimate and choose the figures that can provide accurate and precise measurement.

Leading zero:

The zero which can be present at the start of measurement and the value is known as leading zero. For instance, 00367 the first two zeros (00) known as leading zero and it can’t be a significant figure in this value 3,6, and 7 are the significant figures. Another example is 0.00456089 in this value the leading zero is not a significant figure but the zero which is present in between the digits like 6,0,8 and 9 is referred to as a significant figure.

Spurious:

Spurious digits are those when we do calculations on the instruments then the high-resolution measurement results precisions and the accuracy digits are known as spurious digits.

Another example is if the zero is present in the value after the decimal it can be considered a significant figure like 12.00 then these two zeros are also significant figures and in this value, the total no of significant figures is 4 but if the decimal is not present like 12300 then the last two zero is not considered as significant figure and in this value, the total significant digits are 5. After the decimal point, the zero is also considered as the significant figure for example 1.000 the last trailing zeros are also the significant figures and the total significant figures in this value is 4. But if the decimal is not present like 1000 then this value has only one significant figure and trailing zeros are only a placeholder.

Examples of significant figures:

Some examples of significant figures are given below: 

  • 123790: All digits in this value are known as significant figures.

  • 0.0056:in these digits the leading zero is not a significant figure the last two 5,6 are significant figures.

  • 34986097: all digits are significant figures and the zero which is present inside them like 6,0,9,7 all are significant figures.

  • 1001: all digits are the significant figures.

Rules for determining Significant figures: 

To identify the significant figures from the measurement and for the value, there are some rules. The rules that can help to identify the significant figures are given below:

  • Non-zero digits in the measurement are  to be significant 

  • Between the two significant digits, the zero is also a significant figure.

  • Starting, leading zeros are not a significant figure. 

  • Zero after the decimal point on the right side can also be a significant figure.

  • Trailing zero without the decimal point is not significant. 

Nonzero digits in the measurement are significant figures: 

All non-zero digits in the measurement or the value are significant figures some examples are given below:

  • 9144 all the digits in this value are significant. So the total significant digits is 4.

  • 1.5678 all the digits after decimal or before decimal are considered as significant figures and the total significant digits in it is 5.

  • 568.9 these all digits are significant figures. 

Between the two significant digits, zero is also considered a significant digit: 

The digit zero is not to be considered to be significant but in between the two the significant digit zero also becomes a significant digit some examples are given below:

  • 10054 in this value all digits including zero are referred to as significant figures. 

  • 102.60809 these all digits are considered significant figures the zeros after the decimal point are also considered significant figures.

  • 101.101 in this value all digits are also considered as the significant digits or figures.

Leading zero, and starting zero are not considered significant figures:

The starting or the leading zero is not considered to be a significant figure it can only considered as a placeholder some examples are given below:

  • 000102 in this value last 3 digits 1,0and 2 are called significant but the starting three zeros are not considered to be significant but it is only placeholder or leading zeros.

  • 0.065 the last two digits 6 and 5 are sig figs but the starting zero or zero after the decimal point is not considered a significant figure.

Trailing zero, zero after the decimal point is considered a significant figure: 

The trailing zero, the zero on the right side after the decimal point can considered a significant figure. Some examples are given below:

  • 1.89900 these all digits are considered to be significant digits. In this value, the digits 1,8,9,9,0,0 all are significant figures including the trailing zeros.

  • 0.1200 in this value 4 digits are called significant figure 1,2,0 and 0 are significant figures which are trailing zeros but the first leading zero is not considered as the significant figure.

Trailing zero without a decimal point is considered a non-significant digit: 

The trailing zeros without the decimal point are not considered as a significant figure. some examples are given below: 

  •  19900 the first 3 digits 1,9 and 9 are considered as the significant digits but the last trailing zeros are not to be considered as the significant figure.

  • 1096800 in this value the first 5 digits are considered to be significant but the last trailing zeros are not a significant digit or a figure.

Rounding rules for significant figures:

The rounding-off technique can be used in mathematics in all calculations. In this technique the last digit if it is greater than 5 then it can be added to the previous number. for representing the rounding off number we can use n. To round the significant digit with n there are some rules which are given below:

  • In the measurement value if the last digit is greater or equal to the 5 then we can +1 inti the previous digit. For instance, 1.345 then after rounding the digit the new value is 1.35 and it has 3 significant figures now.

Another example is if we have 5 significant figures like 5.9867 then after rounding off the last digit the new value is 5.987 and they have only four digits in it. 

  • Now if we have the last digit less than 5 then it can’t  be added to the previous number some examples are given below:

       1.563 the last digit is less than 5 so it can’t added 1 to the previous digit and the significant figure in this value is 4. Another example is that 67.91 has the 4 significant figures and they can’t be changed because the last digit value can’t be added.

Numerical value formula:

To calculate the numerical value of significant figures for nonzero significant figure x and for the precision and accuracy p we can use the formula which is given below: 

         10n. Round (x10n) 

Where the n is equal to,

             n=[log 10(x)]+1-p

Precision and accuracy in measurements:

In the measurements precision and accuracy, both are essential. Generally, we can use precision for the stability of the measurements with repeated values and the accuracy used for the closeness to the actual and accurate measurement of the thing and the object. but with time in modern technology and science, both precision and accuracy are termed for trueness or the most closeness exact value of the measurements.  In the scientific community, the accuracy and precise measurement of the object is essential because without accuracy the measurements and problems become more complicated That is why accuracy and precision both are essential for measurements.

Addition and subtraction:

In addition and subtraction, the result of measurements can calculated with the same decimal point before and after the addition and subtraction for example:

12.56+ 0.5=13.1 they have the 3 significant figures in it another example is that

67.9+9 =76.9 and the significant figure in it is 3.

Multiplication and division: 

The result that can be taken from measurement and the result after division and multiplication of values both have the same significant figures some examples are given below: 

4.56 1.4 = 6.384 and we should rounded to 6.4 then they have 2 significant figures like before the division. another example is that 2.44 then it is equal to 9.6 they have also 2 significant digits like before the multiplication or division.

Certainty in significant figures:

In the measurement, certainty means that we confidently know the significant digit in the measurements. This known digit conveys and provides the precision of measurement and is also considered reliable because accuracy and precision are very essential in the measurements.

For example, if we can measure the length of an object with a ruler that has a millimeter marking and the measurement is equal to 24.87 then the digits 2,4,8, and 7 are certain because measurement tools can provide precise and accurate measurements.

Uncertainty in the significant figures:

Rather uncertainty in the significant figures means that which measurements we can take are not precise and accurate and we have doubts about them. When an unskilled person or limited measurement tool is used for measurement then chances of uncertainty increase because a skilled person can take accurate and precise measurements of the object and the high precision measurement tool is also needed. 

For example, if we can measure the length and the measurement is 24.56 then the last digit 6 creates uncertainty because it can be rounded off and the original length can't be measured precisely and efficiently. So that's if we want to remove uncertainty then we again measure the length and then determine the significant figures in it.

Examples of significant figures:

Some examples of significant figures are given below: 

  1. 406.62 all digits in this are significant figures and the total significant figures is 5.

  2. 0.00034 the last two digits are signification figures and the starting zeros are leading zeros.

  3. 12090 all are significant figures and the last zero is only a placeholder.

  4. 74.0 the zero after decimal is also a significant figure the total significant figure is 3. 

  5. 67.08 in this all digits are significant figures and the total is 4.

These are some common examples of significant figures.

Practical problems and their solutions: 

Some practical problems to understand the significant figures are given below:

Problem no 1: Identify the significant figurae: 

Identify the significant figures in the given problems: 

  1. 7696

  2. 0.0074

  3. 690.00

  4. 60.09

  5. 74.0

Solution: 

Solutions to these problems are given below:

  1. All 4 digits are significant figures.

  2. Leading zeros are not significant digits but the last 2 digits 7 and 4 are significant.

  3. All 5 digits including zero after decimal are also considered significant digits.

  4. 6,0,0 and 9 all digits are considered significant figures.

  5. 7 and 4 including trailing zero after the decimal are also considered significant figures. 

Problem no 2: Calculations for significant figures:

The calculation to determine or calculate the significant figures some problems are given below:

  1. 26.7+ 8.1

  2. 62.4 0.04

  3. 2.4+ 9.2

  4. 58.0+ 4.5

  5. 0.056/0.0007

Solutions:

     The solution to these problems is given below:

  1.  34.8 in this value 3, 4, and 8 are significant figures.

  2. 2.496 in this value 4 significant digits are present.

  3. 11.6 in this solution all digits are considered significant figures.

  4. 62.5 in this solution of a problem all digits are significant digits.

  5. 80 are the solution and both are significant figures. 

Problem no 3: Combined operations: 

To determine the significant figures, perform the following operations:

  1. (2.7+ 4) 7.9

  2. (5.6 8.9) + 8

Solution:

Solutions to these problems are given below:

  1. (6.7) x 7.9

=52.93 In this solution, all 4 digits are significant figures.

  1.  (49.84) + 8

= 57.84 In this solution, all 4 digits are significant figures.

Scientific Notation - Definition, Rules, Examples & Problems

Hi friends, I hope you all are well. In this post, we will talk about scientific notation. Scientific notation is an essential tool that scientists and engineers can use. Archemdies presented the idea of scientific notation in the 3rd century BC. His work and scientific notation ideas are based on the novel of time, known as place value.

Scientific notation ideas have evolved over many centuries but are finally represented by Archimedes. In the 16th or 17th century, mathematicians continued to adopt changes in them and invent many other new notable contributions like Rene Descartes who developed algebraic notation. Scientific notation is a way in which we can express large number values in short form in the form of an exponent or a decimal form.

Scientific notation not only simplifies the equation, but it can also help scientists and engineers to do calculations easily. In the United Kingdom scientific notation is also known as standard form or standard index form. Scientific notation is commonly used by scientists and on scientific calculators it is referred to as “SCI” display mode.

What is scientific notation?

Scientific notation in detail is given below: 

Definition:

Scientific notation is defined as:

"it is the simplest way to express the large number into the small number or into in decimal form."

It can used by scientists, mathematicians, and or engineers to simplify the calculation and express the calculation in a very efficient way. In scientific notation, the number is expressed in the product form and they have two factors.

  • A coefficient
  • A power of ten

Generally, the scientific notation is written in:

                N=m 10n

There:

  • N is the number
  • The coefficient is m. It is equal to 1 or less than 10.
  • The integer exponent is n.

Example: 

Some examples of scientific notation are given below: 

  • Covert 89,700 to scientific notation.

  1. Firstly move the decimal to get 8.79

  2. The decimal moved 3 places to the left, then the exponent is 8.

  3. Then the scientific notation is 8.79103

  • Convert 0.0000023 into scientific notation:

  1. Firstly move the decimal to get 2.3.

  2. The decimal moved 6 places, then the exponent is 2.

  3. Then the scientific notation is 2.3106.

Normalized notation: 

We can write any real number equation in the form of m10n in various ways. In the normalized scientific notation, the value of m is 1 or greater than 1 but it is always less than 10 and the value of n depends upon the larger value or decimal place. thus equation 550 can be written as 5.50102. this scientific notation helps to compare the number easily in an efficient way if the exponent value is large that means that the number is normalized as compared to smaller exponents. The order of magnitude can be assumed when we subtract the exponent by separating the numbers.in the table of logarithms, we can use this form of numbers to solve the log questions. The exponent in the normalized equation is negative if the value ranges between 0 and 1 for example: 00.6 then it can be written in 610-2. the exponents may be equal to 10 if the real number value is large like 0.0000000009 then it can be written as 910-10.

In many fields, typically or generally normalized equation is used to express large numbers of values into simple and efficient decimal form. Exponential notation is also referred to as normalized notation. But in different fields, unnormalized or simple notation or equations can be used. Generally, the latter term of notation is more used where the value of m is not suppressed in the range between 1 to 10 and the base of the exponent may be changed or other than the 10.

E notation: 

Generally, calculators or computer programs use small or large number values to present scientific notation or in some calculators, all the numbers are present or configured uniformly. 

The capital letter “E” or the small letter “e: can be used to represent or express the exponent which means “ten raised to the power of”. Typically in all computers or programs scientific notation or normalized notation can be abberived or represented in different styles. But the equation men is the scientific notation like m is the coefficient and the e is base 10 or n is for the exponent and it can be written as men or m10n. For example, 1.000 can be written as 1103 or also written as 1e3.

Engineering notation:

On the scientific calculator, the engineering notation can be written or expressed as “ENG”. The engineering notation is different from normalized notation because the value of exponent n is suppressed in normalized notation. Thus the value of m ranges in 1 ≤ |m| < 1000, other than 1 ≤ |m| < 10. So that's why sometimes the engineering notation is also known as scientific notation.

In engineering notation, the exponent value can be orally read by using prefixes such as nano, pico, Giga, and others. For example, 14.510-9 can as read as fourteen-point-five nanometers and can also be written as 14.5nm.

Significant figures:

The number of digits in the value is used to find the degree of accuracy and precision in a value. 

Significant figures include all nonzeros or zero digits but the first and the last zero digits are not significant figures if zero is present in between the numbers like 1,2,3,4,5 and so on then it is also called a significant figure. Some examples are given below:

  • 456709800 In this value 7 significant figures are present and at the last two zero is only a placeholder and not referred to as significant figures.

  • Then 008809 in these values there are 4 significant figures present and the starting first two zeros are not called significant figures.

So when we convert 123459900 values into normalized or scientific notation then all significant figures are present and the nonsignificant figure is removed as 123459900 has 7 significant figures then it can be written in scientific notation as 1.234599108 or also written as 1.23459900108. thus the advantage of scientific notation is to signify the significant figures efficiently.

Estimated final digit:

In scientific measurement, it is essential to record or measure all known digits from the measurement which can be calculated, and then estimate one or more digits if any information about this digit is acquirable. The estimated digits provided more information and became a significant figure because the estimated digits can provide more accurate and precise information about the leading and the ending digits.

The information that we can take from the estimated digit can help in the notation. This information also helps to choose the final digits or digits that are present in the value. For example, the estimated mass of a proton can be equal to 1.67262192369(51)10-27 kg. But in this value, the error occurs when we estimate the digit inefficiently and can be written as 5.110-37 and this estimated digit can increase the standard error or some other possible errors. 

Rules for scientific notation:

The rules that are used to convert the number into scientific notation are given below:

  •  Identify the coefficient

  • Determine the exponent

  • Base

  • Non-zero integer

  • Positive or negative integer 

  • Add or subtract the coefficient

  • Arithmetic operation with scientific notation

Identify the coefficient:

When we move the decimal point in the value then the original number which becomes the coefficient a is taken like 230000 then the decimal moves in it and becomes 2.3 and the 2 becomes the coefficient in the scientific notation.

Determine the exponent:

Count the number of decimals that we moved in the value and this count becomes the exponent. For example: We have a value of 46000

Then it becomes, 4.6

The total no of decimals that we moved in the value is 4 then the exponent is 4 the value becomes  4.6x104.

Base:

The base of the exponent in the scientific notation is always 10.

Non-zero integer:

The exponent is always a value it is always a non-zero integer like 104 or 108.

Positive or negative integer: 

When we move the decimal from right to left then the exponent integer is positive. Example: 

                 46000 then 4.610+4

When we move from left to right then the exponent integer is negative. Example

              0.00677 then 6.7710-3

Add or subtract the coefficient:

If the exponent is the same then we simply add or subtract them. Because the same exponent can be added or subtracted and also we can multiply or divide with them. For example:

  • 3.4106 + 9.7106

  • The exponent is the same then we add them and then rewrite

  •   3.4+9.7=10.04

  • Then rewrite them into scientific notation

  • 10.04106 then the new scientific notation is 

                     1.004107

Arithmetic operation with notation:

Division:

In the division method, we divide the coefficient and subtract the exponent. An example is given below:

                      81062104= 8106-42

                     =4102

Addition and subtraction: 

To add or subtract the scientific notation, the same exponent must be necessary. And adjust the equation if needed. An example is given below:

                = 2.6103+ 4.0104

 Then firstly we adjust the equation to same the exponent of both equations,

               2.6103= 0.26104

Then add or subtract them,

                   =0.26104+ 4.0104

                  =4.26104

Multiplication:

When we multiply the scientific notation then we add the exponent and multiply the coefficient.

Such as,

                 =(2104) (6102)

Then, 

                   = (26) 104+2

 So,

                 = 12108

Application of scientific notation in the real world:

Real-world applications of scientific notation in different fields are given below:

Chemistry:

Chemists use scientific notation to measure or calculate the atomic size or the atomic level. Such as Avagardo’s number which can be written scientific notation 6.0221023 which can be approximately equal to the one mole in an atom or a molecule.

Astronomy: 

In space, astronomers used scientific notation to calculate the vast distance. Because in space the distance between the moon, the sun, and other planets is vast so that's why to calculate this distance in a short or efficient way astronomers used scientific notation. For example, the distance between the Earth and the nearest star is approximately equal to 4.241013 kilometers. 

Engineers: 

Engineers work on a large scale and calculate the calculation in a very precise and efficient way so that is why they use scientific notation to express large number calculations in short form.  For example, the circumference of the earth which can calculated by engineers is 4.007107.

Physics: 

In physics, scientists can deal with very large and small quantities of measurements so that’s why to write these measurements in an efficient way they can use the scientific notation method. For example, the speed of light is 3.00108.

In education the role of scientific notation:

To become a scientist or for a scientific education understanding the scientific notation is essential. Scientific notation education starts in middle school but is explained in detail at higher levels. To become a scientist and, if we choose the engineering and technology career then the education of scientific notation is compulsory. because it helps them to calculate or, measure the very large or small measurements in a very precise or accurate form.

Challenges and misconceptions:

With the advantages and utility of scientific notation, it also becomes difficult or challenging for beginners. The common misconceptions that can be faced by beginners are given below:

  • Arithmetic operations rules can't be understood or can't be used precisely. 

  • Zero can be confused with exponent.

  • The decimal point can't be placed properly. 

  • Rules which are used for scientific notation can be misunderstood.  

Strategies that can be used to manage or overcome these misconceptions or challenges include:

  • Understand the rules of scientific notation step by step and follow instructions.

  • Try to solve numerous examples without help. 

  • Understand the rules and solve the arithmetic operations.

Future perspectives:

With the development of modern science and technology, the use of scientific notation is also increased and it can also be improved from time to time. In modern science and technology, very large and small measurements can be calculated so that’s why the scientific notation method is used to express calculation effectively and accurately because scientific notation also helps to overcome or analyze errors in calculations. 

Examples:

                   Examples of scientific notation are given below:

  • The mass of the electron is approximately equal to  0.000000000000000000000000000000910938356 kg 

But we can write in scientific notation as,

                                                 =  9.10938356×10−31

  •  The circumference of the earth is approximately equal to 40000000m

    Then we can write in scientific notation as

                             =   4107

  • The distance between the sun and earth is approximately equal to 149,600,000 kilometers

             In scientific notation, it can written as:

                      =1.496108

  • The mass of hydrogen is approximately equal to 0.00000000000000000000000167kg

In scientific notation, it can be written as,

                           =1.6710-27

  • The value 564300 can be converted into scientific notation and written as

                       =5.643105

Problems: 

Some problems are given below:

Conversion:

      Convert the following problems into scientific notation:

  • 456800

  • 0.005544

  • 98076

  • 5544320

  • 0.00000000009

  • 9888800000

Solutions:

             Solutions to these problems are given below:

  • 4.568105 

  • 5.54410-3

  • 9.8076104

  • 5.544320106

  • 910-11

  • 9.8888109

Multiplication:

                Multiplication problems are given below:

  • (2108 ) (4104)

  • (2.0104) (2102)

Solution:

     Solutions to these problems are given below:

  • (24) 108+4

=81012

  • (2.02) 104+2

=4.0106

Division:

                 Division problems are given below: 

  • 5.61097.0103

  • 8.41052.0102

Solution:

A solution to these problems is given below:

  • 8.0105

  • 4.2103

Addition and subtraction:

Perform the following operations with numbers in scientific notation:

  • (5.0104)+(2.5104)

  • (6103) + (4.0103)

Solution:

A solution to these problems is given below:

  • 7.5104

  • 6103

SI Derived Units (International System of Units)

Hello friends, I hope you are all good. In our previous lecture, we discussed the SI Base Units in detail and today, we are going to discuss the units derived from these base units. In 1960, the International Committee conference was held and they presented the measurement units that are used to measure all quantities worldwide.SI units are used to make accurate and precise measurements.

SI units are the set of seven basic units called base units and all other units are derived from these base units and called derived units. A set of seven base units is used to measure the physical quantities but derived units are used to measure the complex quantities other than physical quantities.  SI units play an essential role in modern technology and sciences.

Basic SI units: 

The basic SI units from which the other units are derived are given below:


            Units 

            Symbol

            Measure 

meter

m

length

Kelvin 

k

Thermodynamic temperature 

Ampere 

A

Electric current 

Second 

s

Time 

candela

cd

Luminous intensity

Kilogram 

kg

mass

mole

mol

Amount of a substance 

These units are the building blocks of all others known as derived units. Derived units are the combination of these base units in the form of an algebraic combination.

Coherent derived units: 

SI-derived units which are also known as coherent-derived units are derived from base units which can be expressed in ratio, product, or exponential form. Some derived units have dimensions but some do not because their demission cancels through their ratio or product.

Derived units are used to measure the complex quantity. Derived and coherent derived units have specific names, symbols, units, and dimensions. All derived units have dimensions except steradian or radian. 22 derived units, their names, symbols, and dimensions are given below:


Derived quantity 

Specific name

symbol

Specific symbol

SI base units 

Other equivalent units

Magnetic induction, magnetic flux density 

tesla

T

Jm

Wb/m2

kg⋅s−2⋅A−1

Plane angle 

Radian 

α,𝛃,ℽ

rad

m/m

      —

Solid angle 

Steradian 

Ω

sr

m2/m2

      —

Catalytic activity 

Katal 

ζ

kat

mol/s 

mols-1

Illuminance 

lux

Ev

lx

lm/m2

lm.m-2

Absorbed dose

Gray

D

Gy

J/kg

m2⋅s−2

Inductance 

henry

L

H

Wb/A

kg⋅m2⋅s−2⋅A−2

Pressure, stress 

pascal

р

Pa

N/m2

kg⋅m−1⋅s−2

Electric resistance 

ohm

R

Ω

V/A

kg⋅m2⋅s−3⋅A−2

Celcius temperature 

Degree Celcius 

t,δ

k

k

force, weight

Newton 

F

N

Kg m/s2

kg⋅m⋅s−2

Frequency 

hertz

f,v

Hz 

1/s

s-1

Energy, work, heat 

Joule 

E

J

N/m , w/s

kg⋅m2⋅s−2

Dose equivalent  

sievert

H

Sv

J/kg 

m2⋅s−2

Luminous flux 

lumen

Փv

lm

cd/sr

cd

Activity of radionucleotide 

becquerel

A

Bq

1/s

s−1

Magnetic flux 

weber

Փ

Wb 

V/s

Vs−1

Capacitance 

farad

C

F

C/V

kg−1⋅m−2⋅s4⋅A2

Electric charge 

Coulomb

Q,q 

C

s/a

s.a

Electric potential difference 

Volt 

Vab

V

W/A

kg⋅m2⋅s−3⋅A−1

Electric conductance 

Siemens

B

S

A/V

kg−1⋅m−2⋅s3⋅A2

Applications of SI units in different fields: 

SI units are used in different fields in chemistry, kinematics, thermodynamics, photometry, kinematics, electromagnetism, or in mechanics. The details are given below:

Photometry:


Derived quantity 

Name

Symbol

SI units 

Luminance energy

Lumen second 

lm.s

s.cd

Luminance 

Candela per square meter

cd/m2

m−2⋅cd

Luminous exposure 

Lux second 

lx.s

m−2⋅s⋅cd

Luminous efficacy

Lumen per watt 

lm/w

m−2⋅kg−1⋅s3⋅cd

Chemistry:


Derived quantities 

Symbol

Name 

Electric charge 

C

Coulomb 

power

W

watt

frequency

Hz

hertz

Force 

N

newton

Voltage 

V

volt

area

m2

Square meter

Pressure 

Pa

pascal

Volume 

m3

Meter cube

Energy 

J

joule

Kinematics:


Derived quantities 

Names 

Symbol

speed

Meter per second 

m.s-1

Jounce 

Meter per fourth second

m.s-4

Angular acceleration

Radian per second square

rad.s-2

Volumetric flow

Cubic meter per second

m3.s

jolt

Meter per cubic second 

m.s-3

acceleration

Meter per second square

m.s-2

snap

Meter per fourth second

m.s-4

Angular velocity

Radian per second

rad.s-1

Frequency drift 

Hertz per second 

hz.s-1

Thermodynamics:


Derived quantities 

Names 

Symbols

Thermal expansion 

Per kelvin 

k-1

Specific entropy

Joule per kg per kelvin

J.kg-1.k-1

Thermal resistance

Kelvin per watt

k.w-1

Heat capacity

Jolue per kelvin 

J.k-1

Temperature gradient 

Kelvin per meter

k.m-1

Thermal resistance 

Kelvin per watt

k. w-1

Importance of derived units in physics:

Derived units play a very vital role in physics and many other fields for accurate and precise measurement and also help to understand the physical phenomena. The building blocks of SI units are seven basic units by combining them the all other units derived. Derived units play an essential role in modern science and technology to measure stable and precise measurements.

The importance of derived units in physics is given below: 

  • Standardization and consistency

  • Efficiency in scientific computation

  • Practical applications

  • Simplification of complex quantities 

  • Enhanced power solving

  • Facilitation of understanding and communication

  • Interdisciplinary relevance 

Details of the importance of derived units are given below:

Efficiency in scientific computations:

The use of derived units enhances computational efficacy in physics. Calculations involving derived units are often more straightforward than those using only base units. For instance, the 

Unit watt for power simplifies calculation ]s involving energy and time, eliminating the need for repeated conversions from base units. This efficacy is particularly important in complex calculations, simulations, and models, where reducing the number of steps can significantly impact the accuracy and speed of results.

Interdisciplinary relevance:

Derived units are not confined to physics alone but are used across various scientific disciplines, fostering interdisciplinary research and applications. For instance, the coulomb, a unit of electric charge, is crucial in both physics and chemistry. The use of common derived units across different fields facilitates collaboration and integration of knowledge, leading to achievements in areas such as materials science, biophysics, and environmental science. This interdisciplinary relevance underscores the versatility and universality of derived units in scientific inquiry.

Standardization and consistency:

One of the foremost reasons derived units are vital in their role in standardizing measurement globally. The SI system, established and maintained by the International Bureau of weights and Measures (BIPM), ensures that measurements are consistent and universally accepted. Derived units such as newton(N) for force, the joule (J )for energy, and the watt(W) for power, are constructed from base units like the kilogram(kg), meter(m), and second(s). This standardization is crucial for scientific communication, allowing researchers from different countries and disciplines to compare results and collaborate effectively on confusion or the need for conversion factors. 

Practical Applications:

In practical and industrial contexts, derived units are designed to be more user-friendly for real-world measurements. For example, the hertz(Hz) is used to measure frequency, providing a more practical and comprehensible unit than cycles per second. Similarly. The use of derived units like the lumen(lm) for luminous flix or the sievert (Sv) for radiations enables more precise and accessible measurement and regulation in various industries, including healthcare, engineering, and environmental monitoring.

Facilitation of understanding and communication:

Derived units provide a clearer and more intuitive understanding of physical phenomena. For example, energy is measured in joules, which convey specific physical meaning, more straightforwardly than its base unit equivalent. This clarity extends to educational settings, where students can grasp complex concepts more easily when they are expressed in familiar derived units. additionally, using standardized derived units in scientific literature and presentations ensures that findings are communicated effectively, fostering a shared understanding among researchers.

Simplification of complex quantities:

Many physical quantities are inherently complex and can't be conveniently expressed using only base units. Derived units simplify these expressions, making them more manageable and intuitive. For instance, pressure is commonly expressed in pascals(Pa) rather than its base unit form of kg/ms-2. This simplification is not merely a matter of convenience but also aids in understanding and interpreting physical concepts more readily. It allows scientists and engineers to work more efficiently, reducing the potential for error and misinterpretation.

Enhanced problem-solving:

Derived units play a crucial role in problem-solving by aiding in dimensional analysis, which involves checking the consistency of equations. Dimensional analysis ensures that equations are dimensionally consistent, meaning that both sides of an equation have the same units. This technique is fundamental in verifying the correctness of quotations, deriving new relationships, and identifying potential errors. For example, ensuring that the units on both sides of Newton’s second law (F=ma) match confirms that the equation is dimensionally consistent and physically meaningful.

Application of derived units: 

Some applications of derived units are given below:

Joule(J): 

This unit are used for heat, energy, and work. Their application in physics is given below:

  • Mechanics: the work which is done by a person or an object can be measured in joules. This concept is also used to understand the potential and the kinetic energy.

  • Thermodynamics: according to the first law of thermodynamics the energy that can be expressed in joules can't be created or can’t be destroyed and the energy in the form of heat can always be measured in joules.

  • Electricity: in the electrical system the energy which can be used in the form of electricity can be measured in joules because work is also done in it.

Watt(W):

These units are used for power, their application in physics are given below: 

  • Mechanical systems: the power that can be consumed in engines or different mechanical systems can be measured in watts.

  • Electrical engineering: in our daily life or households like bulbs, ovens, and other electronic devices, the electric energy that can be consumed is measured in watts. 

  • Thermodynamics: In cars engines, and other electronic devices which consume electrical energy can be measured in watts.

Volt(V): 

  These units are used to measure electric potential, and their application in physics is given below:

  • Power distribution: the voltages that can be distributed to the power line can be measured in volts. 

  • Electronics: the electrical devices like capacitors, diodes, and others that can distribute the voltages. These voltages which can be distributed are measured in volts. 

  • Electric circuits: in electric circuits, the potential that can be distributed is measured in volts.

Tesla(T):

These units are used to measure the magnetic flux density, their applications in physics are given below:

  • Physics research: In physics research when high magnetic fields are used then these field strengths can be measured in teslas. 

  • Electromagnetism: the magnetic field strength in the magnets can be measured through teslas.

  • Medical imaging: In the medical field medical devices like MRI machines have also a strong magnetic field which can also be measured in teslas.

Ohm(Ω): 

This unit is used to measure electric resistance, their applications in physics are given below:

  • Thermistor: temperature-sensitive resistors use temperature and resistance both and to measure or control the temperature ohm is used.

  • Circuit design: in electrical circuits where electric current is passed resistance is also present to measure the resistance we can use ohm.

  • Material science: to manufacture the electronic device, an ohm is used to measure the resistance.

Henry(H):

This unit is used to measure inductance, their applications in physics are given below:

  • Radiofrequency: In radio when the tune is played then the frequencies are matched because during their manufacturing frequencies are measured in hertz.

  • Electrical engineering: To make inductors and coils of inductance to make a strong magnetic field Henry is used to measure the inductance.

  • Power supply: to supply the power current smoothly without changing in current and voltage inductors are used.

Farad(F): 

This unit is used to measure capacitance, their applications in physics are given below:

  • Energy storage: capacitors which are used in electrical devices are used to store energy and the farad is used to measure the capacitance of a capacitor. 

  • Communication systems: In television, radios, and other electronic devices capacitors are used to store energy.

Newton(N):

This unit is used to measure force, their applications in physics are given below:

  • Aerospace: Newton is used to find or determine the thrust and friction that are produced by engines during flight.

  • Classic mechanics:  Newton is used to determine the forces that are produced by an object or a person. Newton also presented 3 laws.

  • Engineering: the engineers who build the buildings and bridges calculate the forces to ensure that these can bear stress or not.

Pascal(P):

This unit is used to measure pressure, applications of Pascal are given below: 

  • Engineering: The engineer used Pascal to calculate the stresses of the material and then used the material.

  • Fluid dynamics: Blood pressure, atmospheric pressure, and all fluid pressure can be measured and calculated through Pascal.

  • Meteorology: to measure the climate and weather Pascal is used.

Coulomb(C):

This unit is used to measure electrical charge, their application in physics are given below:

  • Capacitors: capacitors are used in electrical devices to store energy and to maintain the current flow.

  • Electrostatics: in the electrostatic experiments coulomb are used to measure the electric charge that flows through them.

  • Batteries: in batteries, the charge stored that is used after completing the charging.

Conclusion: 

Derived units are used in various fields to measure complex quantities and physical phenomena that can't be measured by using the base quantities. Derived units like joule, watt, kelvin, coulomb, Pascal, and all others are derived from basic seven base units in the form of exponent. Now derived units are used in modern technology and sciences. Scientists used these units to measure the different quantities precisely and accurately. From time to time, the SI system can also continue to adopt the changes and present more suitable and precise units for the measurement of the quantities. The SI system adopts many changes in its units and redefines them.

SI Units(International system of units)

Hi, friends. I hope you are all well. Today we will discuss the SI ( International system of units) in detail. An international committee conference held in 1960 concurred on a set of definitions used to describe the physical quantities. This committee and the founded system are called System International (SI).

SI units are the measurement systems used generally to measure the standards.SI units play a vital role in measuring standard quantities in scientific and technological research.SI units are a set of basic 7 base units from which derived units are defined.SI units also play a vital role in modern metrology and now they become a part of the foundation of modern science and technology.SI units can be categorized into three types:

  • Base units
  • Supplementary units
  • Derived units

Now we will discuss what SI base units are, their definitions, importance, and applications in detail.

What are SI base units?

SI base units are the basic standard units explained by an international system (SI) of units. SI base units are known as the building block of the international system of units because all other units are derived from these basic standard units.

Base units are used to express the base quantities. And the other units are used to express the derived quantities which are derived from base quantities and units. The physical quantity and units are:

These SI units were globally accepted for measurement of the physical quantities. 

The basic definition of SI base units: 

The basic definitions of the SI base units are given by the System international unit in detail below:

Unit 

Measure 

Symbol 

Typical symbols

Definition 

meter

length

m

L,x,r, etc 

In the SI unit system the, meter is the unit of length and it is defined as in 1/299, 792,458 seconds the light travels in a vacuum. In 1983 this definition was presented and it is based on the fundamental constant of nature, the speed of light. meter is the most precise unit which are used in the measurement.





second

Time 

s

t

The unit of time is second and it is defined as the transition changing between the two levels of hyperfine at the ground state of the cesium atom. This definition was presented in 1967 and also defined as 9,192,631,770 duration of radiation in between the transition. Now to measure the accurate time the unit second is used in science.


Kilogram 

mass

kg

m

SI of mass in kilogram it is defined by IPK as the international prototype of kilogram and in simple words, it is defined as the mass of a substance in thousand grams. Now this unit is widely used in measurements of the mass of an object.


Ampere 

Electric current 

A

I, i

The unit of the electric current is ampere. The definition of unit electric current is based on the charge of a proton and the elementary charge e, and conductor forces. But with time it can change and be explained on the fixed numerical value of elementary charge. Now the precise and accurate measurement of electric current in the unit ampere can be used.


kelvin

Thermodynamic temperature

k

T

The unit of thermodynamic temperature is kelvin. It was defined based on the Boltzmann constant(k) and also relates to the average kinetic energy of the gas. but now it can be defined on the basis of a fixed numerical value of the Boltzmann constant to measure the accurate temperature with the help of their unit Kelvin.


candela

Luminous intensity 

cd

lv

The SI unit of luminous intensity is candela and it is used to measure the power of light. It is defined as measuring the radiation of the frequency of 540x10hertz which is emitted from monochromatic sources and also measures the radiant intensity of 1/683 watt per steradian. Now to measure the accurate and exact power of light candela unit is used.

mole

Amount of a substance

mol

n

The SI unit of the amount of a substance is mole.it is defined as atoms or molecules in the carbon-12 isotopes, which is based on Avagord’s number 6.022x10 power 23. But now it is based on the fixed numerical value of Avagord’s number to measure the accurate amount of the substance with the unit mole.


These definitions are the old and basic definitions but with time and with more research these definitions can be revised and new definitions of these base units are presented.

Revised and new definitions of SI base units:

In 2016 November 16 the old and basic definitions of base units can be revised but it can be effective from 2019 May 20. The redefinition of the meter can be revised by understanding the physical artifact and it is not based on the property of nature. Other basic units like candela, kilogram, mole, and ampere can be connected to the revised definition of kilogram which is presented by an international prototype of the kilogram, by storing the cylinder of platinum-iridium in a vault near Paris.

The revised and new definitions of SI base units are given below.

Units

measures

Dimensions 

Symbol

Revised and new definitions 

Origin 

Candela 

Luminous intensity 

J

cd

The SI unit of luminous intensity and the power of light is candela, symbol cd. It is stated and based on the fixed numerical value of luminous efficacy of 540×1012 Hz frequency of monochromatic radiation. It can also expressed in W−1 or also in kg−1 m−2 s3


The principle and the base of the candle power are the standard properties of burning candles which can emit light traditions through burning. 


Ampere

Electric current 

I

A

The SI unit of electric current is the ampere, symbol A. it can based and taken from the fixed numerical value of e (elementary charge) which is equal to 1.602176634×10−19 and also expressed in units C and s.




Specifically the unit ampere at internationally defined and based on the electrochemical. In the electrochemical process, the current is required to store 1.118 mg of silver per second to form the solution of silver nitrate.


Mole

Amount of a substance 

N

mol

The SI unit of the amount of a substance is a mole and the symbol is mol. 

Mole is based on Avagord’s numbers so one mole is equal to  6.022 140 76 × 1023

And this value is the fixed numerical value of Avagord’s number which can’t be changed. And their unit is per mol. To express the substance the symbol which is used is n. N is for the elementary entities that can be specified and the elementary entities may be an atom, molecule, ion or electron, or a group of particles.


1 g/mol is equal to the molecular weight which is divided by the molar mass.



meter

Length 

L

m

The SI unit of length is meter, symbol is m. it is defined on the principle of the speed of light in vacuum c which is equal to 299792458 and expressed in unit ms-1.


The median arc through Paris is measured and the total distance which is measured is equal to 1/100000000 from Earth to the north pole.




Kilogram 

mass

M

kg

The SI unit of mass is the kilogram, the symbol is kg. It is based on the fixed numerical value of the Planck constant which is represented by h and equal to 6.62607015×10−34 and their unit is Js.

One liter is equal to thousands of m3. The mass of water is equal to the temperature of melting ice.




Kelvin 

Thermodynamic temperature 

k

The SI unit of thermodynamic temperature is kelvin, symbol is k. It can also defined based on the Boltzmann constant the fixed numerical value which is equal to 1.380649×10−23 

And their unit is  JK-1.

The Kelvin and the Celsius scale both are used in thermodynamicscic temperature and 0k is equal to the absolute zero.




Second 

Time 

T

s

The SI unit of time is second, symbol s. The fixed numerical value of cesium defined it. Because the ground state hyperfine transition frequency of cesium is equal to 9192631770 and its unit is hertz which is expressed in s-1.


Each day has 24 hours and each hours have 60 seconds and 1 second is equal to the 24x60x60 of each day. 


Application and Importance: 

Application and importance of all seven base units in detail are given below: 

Meter:(the unit of length)

  • Physics and engineering: to measure the accurate length in constructing the building and in designing the machinery.

  • Astronomy: to measure the distance between the objects and the measurement is precise and accurate.

  • Everyday life: in our daily life meter is used to measure the length of an object and also measure the distance or the plot size.

Candela:(unit of luminous intensity)

  • Lighting industry: to measure the precise and accurate luminous intensity which is important in designing and creating a lighting system.

  • Cinematography and photography: to achieve the effective and desired visual effects accurate measurement of light is essential.

  • Vision science: to understand or design human vision aids measurement of luminous intensity is very essential.

Second:(the unit of time)

  • Synchronization: accurate and precise measurement of time is very important for clocks at the global level and also shows an impact on telecommunication and in many other social systems.

  • Daily life: in daily life time measurement is essential to make a schedule and to do work on their given time.

  • Physics experiment: to measure the velocity, speed, and distance time measurement is essential to do work or experiment on time.

Kilogram:(the unit of mass)

  • Medical field: to make the dosages and the multivitamins the mass of a substance is essential to measure because if the mass is increased to make a low dose of medicine then it can show very adverse effects.

  • Science and industry: to make the chemicals in industry accurate and precise measurement of a substance is very important. 

  • Trade and commerce: for fair trading the measurement of mass is essential.

Mole:(the amount of substance)

  • Environmental science: in the environment, the amount of pollutants and harmful gases can be measured through a mole.

  • Chemistry: In the chemical reaction of chemistry the mole is the essential and fundamental part of a reaction or the chemistry experiment

  • Pharmacology: in the pharmaceutical industry the precise and accurate measurement of mole is essential to make chemicals and medicines.

Ampere:(the unit of electric current)

  • Medical equipment: many medical machines like x-ray machines, MRIs, and CT scans can measure the precise measurement of electrical current.

  • Electrical engineering: to measure the precise and accurate current in electronic devices. 

  • Power system: to distribute the electric current in the electrical system and to operate the power system the measurement of electric current is essential. 

Kelvin:(the unit of thermodynamic temperature)

  • Industrial process: in industries to manufacture the material the accurate and precise measurement of temperature is vital.

  • Climate studies: the global and climate temperature change every time and to measure the accurate temperature of climate, the temperature can be measured accurately.

  • Scientific research: in physics, chemistry, and many other science subjects in which we can perform experiments, the measurement of temperature is essential to run the process of experiment. 

Interrelationship and derived units:

The foundation of all SI units in the SI system are the seven base units which are interlinked. To measure the complex and difficult physical quantities derived units are used which are a combination of seven base quantities. Some examples are given below: 

  •  Watt(W): this is the unit of power and can derived from the base unit (J/s).

  • Newton(N): this unit is used for force and derived from the base unit meter, seconds, and kilogram.

  • Joule(J): this unit is used for energy and derived from base units like seconds, kilograms, and meters.  

These are some examples of derived units that are derived from the combination of different base quantities.  

The evolution and future of SI units: 

The SI unit's definition can be changed with time to increase precision and stability. because these units can be used in modern science and technology and also in meteorology processes.

The SI system can do more research to evolve modern technology and discover more precise and effective results of their research to make the bright future of SI units. Potential future changes could involve redefining units based on even more fundamental principles or developing new measurement techniques that further enhance precision and accessibility.

Conclusion:

The international system of units(SI) plays a vital role in physics, scientific research, pharmaceutical industries, and our daily lives. The seven base units are the fundamental and the foundation of the international system of units. These units help to measure all the quantities in a very effective and the results are precise and accurate. With time science and technology progress the si system also tries to maintain more precise and relevant changes in their research.

Advanced Manufacturing Materials for PCB

Hey there, I hope you are having a good day. Printed circuit boards (PCBs) are a popular topic in the electronic world and we also know that PCBs have revolutionized circuits. They not only provide a solid base but the material used in the PCBs helps the circuit to function properly by protecting the circuit from factors like external radiation. These are present in different materials that divide the working, stability, and reliability of the circuit. In recent years, there has been a significant change in the types and strength of PCBs and this depends on the materials used in the manufacturing of these boards. We are interested in studying the advanced materials used in the manufacturing of PCBs and knowing the right type of material for the right circuit.

In this article, we’ll start from the basic introduction of the advanced material and will try to understand why it is better to replace the traditional material with the advanced one. After that, we’ll see some important categories of the advanced materials used in the production of PCBs that are important to meet the needs of the latest technologies.

Where to order PCB?

Before going forward, let me first tell you where you manufacture your PCBs with these materials. PCBWay Manufacturing House provides almost all of these materials for PCB manufacturing. PCWay provides the best services when it comes to PCB designing. I personally use PCBWay for all my PCB orders and always get the best results.

In order to place your order in PCBWay, click on the Order Now Button and insert your PCB details. On that PCB details page, you can select the PCB material for your board. The order page of PCBWay is shown in the below figure:

Advanced Material of PCBs

The transformation of PCBs in recent years is because of the high quality and advanced materials used in manufacturing and this not only has improved the life span of the PCBs but also has a major impact on the circuit performance. The advanced materials are referred to as:

"The advanced materials for PCB manufacturing are the new material or the improved existing materials used in the manufacturing and design of the latest PCBs that help to meet the requirements of the advanced PCBs."

With the advancement in technologies, there is a requirement for faster, smaller, and more efficient electronics, and that in return, has enhanced the need for advanced PCBs. These requirements are fulfilled by using the advanced and more efficient material that helps to meet the need of the time. These materials are responsible for innovating the PCBs and these are not only the trend but are the essentials that are required to meet the requirements of contemporary electronic applications.

The advanced materials are better in performance and provide high-speed data transmission from one end to the other which is the main focus of the advanced digital electronic equipment. 

PCB Advanced Material Examples

Here is a list of almost all the important advanced materials that are extensively used in the PCBs nowadays and play a crucial role in the improvements of the PCB industry:

Advanced PCB High-Speed Laminates

The traditional material is not able to overcome the advanced problems and boundaries of the bandwidth. The high-frequency circuits are introduced in the market that perform complex duties and these circuits are successful only when high-frequency PCBs are used. For this purpose, high-speed laminates are used for the manufacturing and design of the PCB. these cutting-edge laminates are the new generation of high-frequency materials for PCBs tailored for high-frequency applications.

High-Speed Laminates Properties in PCB

  • These laminates have an exceptionally low dielectric constant (Dk) that ensures minimal signal distortion. This property makes the PCB capable of dealing with the speed of light making the circuit work faster and better to match the new trends and requirements of the technology. 

  • The minimal signal loss helps this material to provide another feature to PCB which is the negligible dissipation factor (Df). It maintains the signal integrity and provides low heat dissipation. One must be kept in mind that it results in efficiently dealing with the heat problems of the circuit. 

  • The thermal stability of the high-frequency laminates is a plus point that helps to achieve the advanced level outputs from the circuit. These laminates have the physical properties to bear the high temperature without causing any change in their shape.

Examples of High-Speed Laminates

The following are suitable examples that are widely used in PCBs:

  • Rogers RO4000 series

  • Taconic CERFREE

  • PTFE (Polytetrafluoroethylene)

  • FR-4 

  • Isola Isola-Tate FR-408

  • LCP (Liquid Crystal Polymer)

Metal Core PCBs as Advanced PCB Material

The metal core PCBs (also known as the MCPCBs) are the specialized PCBs that has the metal base as the substrate. The most common metal-based PCB types are listed below:

  • Aluminum

  • Copper

  • Steel alloy

Out of these aluminium-based PCBs are the most cost-effective. One evidence of this statement is, that it has high heat resistance therefore, such PCBs have a long life. Hence, the low heat dissipation results in the better performance of the circuit for a long time.

On the other hand, if the user wants high performance then the copper-based MCPCBs are a better option than the previous one. Copper is considered one of the most reliable conductors because of the physical arrangement of its atoms therefore, using it in the PCB is the best way to get the highest performance. This is the most commonly used material for the PCBs but it is more expensive the the aluminum PCBs.

Another important metal in regard is steel which is harder than the other two options mentioned before. Because of the tightly packed structure, this type of PCB has less conductivity but the plus point is, that these have excellent heat dissipation.

As a result, the specific type of the metal core PCB is used for the specific type of the circuit by keeping the thermal and other characteristics of the PCBs. These types of materials are used in PCBs because they have features like heat dissipation, less distortion, good dimensional stability, etc.

Advanced Flexible Material for PCBs

The flexible PCBs are one of the most trending type of PCBs that have the ability to make space in any type of the circuit and does not cause any major performance change. The advanced technology has made the circuit small and more flexible, therefore, there is a need for the PCB that is flexible and can bear the load of the high calculation and processing. These are made with lightweight, thin, and flexible materials and lead to a high range of applications in all types of circuits.

These PCBs are made on different scales of size and thickness and can be bent like a rubber therefore, are considered the ideal PCBs for wearables and other such technologies. The most commonly used flexible materials for PCBs are

  • LCP (Liquid Crystal Polymer)

  • PEN (Polyethylene naphthalate)

  • PET (Polyethylene Terephthalate)

  • PI (Polyimide)

  • PTFE (Polytetrafluoroethylene)

  • Flexural FR-4

  • Coverlay films (PI, PET, etc.)

  • Metal foil (copper, aluminium)

  • Adhesives (acrylic, epoxy)

Hence in this way, we have seen different type of advanced materials that are used in the PCBs and are making them more efficient and up to date. We started with the basic introduction of the advanced materials in the PCBs and then we understood different types of the advanced material that is revolutionising the PCB industry. The high-speed laminates, metal core PCB, and the flexible materials in the PCBs are important materials in this regard. If you know other such materials that are most common and suitable for advanced PCBs then share with us through the comment section.

Top Decentralized Crypto Wallets in 2024

As the cryptocurrency market continues to evolve, the importance of secure and user-controlled wallets has never been greater. Decentralized wallets, which allow users to retain full control over their private keys, are becoming the go-to choice for crypto enthusiasts. 

These wallets not only provide enhanced security but also offer greater privacy and compatibility with decentralized applications (DApps). This post will explore the top five wallets available in 2024 to help you pick the best decentralized crypto wallet for your needs. 

Wallet

Supported Cryptos

Security Features

User Control

Compatibility with DApps

MetaMask

Ethereum, ERC-20

Password, seed phrase, open-source

Full control

High

Trust Wallet

Multiple

Encryption, biometric authentication

Full control

High

Mycelium

Bitcoin, Ethereum

Cold storage, encrypted backups

Full control

Medium

Exodus

100+

Encryption, password protection

Full control

Medium

Ledger Live

Multiple

Hardware security, 2FA

Full control (with hardware)

High

Why Choose a Decentralized Wallet?

Decentralized wallets offer several advantages over their centralized counterparts:

Security Advantages

Decentralized wallets ensure that only the user has access to their private keys, reducing the risk of hacking and theft. Since there is no central authority managing the keys, the potential for large-scale breaches is minimized.

User Control and Privacy

With decentralized wallets, users maintain full control over their funds and personal information. This autonomy aligns with the core principles of cryptocurrency, promoting financial freedom and privacy.

Compatibility with Decentralized Applications (DApps)

Decentralized wallets are designed to interact seamlessly with DApps, enabling users to participate in the growing ecosystem of decentralized finance (DeFi), gaming, and other blockchain-based applications.

Top Decentralized Crypto Wallets in 2024

To help you choose the best wallet for your needs, we've evaluated the leading decentralized crypto wallets based on their features, security protocols, user control, and compatibility.

MetaMask

MetaMask is a widely used browser extension and mobile wallet that supports Ethereum and ERC-20 tokens. It offers a built-in token exchange, allowing users to trade cryptocurrencies directly within the wallet.

Security Protocols:

MetaMask uses secure password and seed phrase systems to protect users' private keys. The wallet's code is open-source, enabling the community to audit and enhance its security. Additionally, MetaMask can integrate with hardware wallets for added security.

User Control:

As a non-custodial wallet, MetaMask ensures that users have full control over their private keys. This autonomy allows users to manage their assets without relying on third parties.

Compatibility:

MetaMask is highly compatible with Ethereum-based DApps, making it a popular choice for users engaging in DeFi and other blockchain activities.

Trust Wallet

Trust Wallet is a mobile wallet known for its broad support of multiple cryptocurrencies. It allows users to store, send, receive, and stake a variety of digital assets. Trust Wallet also integrates with DApps and DeFi platforms.

Security Protocols

Trust Wallet employs encryption and biometric authentication to secure user data. As a non-custodial wallet, it ensures that users retain control over their private keys, which are stored locally on their devices.

User Control

Users have full control over their private keys and can manage their funds independently. Trust Wallet provides a secure and private environment for cryptocurrency transactions.

Compatibility

Trust Wallet supports a wide range of cryptocurrencies and integrates seamlessly with various DApps and DeFi platforms.

Mycelium

Mycelium is a mobile wallet that supports Bitcoin and Ethereum. It offers advanced features such as hardware wallet integration, spending accounts, and local trading options.

Security Protocols

Mycelium provides robust security features, including cold storage integration and encrypted PDF backups. Users can connect their wallet to a hardware wallet for added protection.

User Control

As a non-custodial wallet, Mycelium ensures that users have full control over their private keys. This feature is especially appealing to users who prioritize security and privacy.

Compatibility

Mycelium supports Bitcoin and Ethereum and offers compatibility with hardware wallets, enhancing its security and usability.

Exodus

Exodus is a desktop and mobile wallet known for its beautiful design and ease of use. It supports over 100 cryptocurrencies and offers an integrated exchange for trading. Exodus also provides portfolio tracking and management tools.

Security Protocols

Exodus is a non-custodial wallet, meaning users control their private keys. The wallet uses secure encryption to protect users' data. While it does not offer two-factor authentication, it provides password protection and regular security updates.

User Control

Exodus allows users to manage their private keys and funds independently, providing a secure environment for cryptocurrency transactions.

Compatibility

Exodus supports a wide range of cryptocurrencies and integrates with various exchanges, offering flexibility and convenience for users.

Ledger Live

Ledger Live is the companion app for Ledger hardware wallets, which are renowned for their security. It supports a wide range of cryptocurrencies and offers features such as staking, lending, and buying crypto. Ledger Live provides a comprehensive portfolio overview, making it easy to manage multiple assets.

Security Protocols

Ledger hardware wallets store private keys offline, protecting them from online threats. Ledger Live enhances this security with features like password protection and two-factor authentication. The combination of hardware and software security makes Ledger one of the safest options available.

User Control

While Ledger Live is used in conjunction with Ledger hardware wallets, users maintain full control over their private keys. This combination of hardware and software provides robust security and user control.

Compatibility

Ledger Live supports a wide range of cryptocurrencies and integrates seamlessly with various DeFi platforms and exchanges. 

Nonbank 

The fintech world has immense potential, and Nonbank is here to prove that. Nonbank is an online platform that aims to be your finance buddy, allowing you to track and easily manage all your digital assets. 

Nonbak is a non-custodial wallet that allows you to keep all your bank accounts, crypto wallets, and exchanges in check. The first feature the company is set to release is the Tron wallet. It is claimed to be the best multi-chain wallet that is easy to use. You can sign up to get early access to the platform and follow Nonbank on X for updates. 

Final Say

Choosing the best decentralized crypto wallet depends on what you need. Whether you care most about security, control, or using DApps, there's a wallet that fits your needs. Picking the right one helps keep your digital assets safe and gives you control in the changing world of cryptocurrency.

Syed Zain Nasir

I am Syed Zain Nasir, the founder of <a href=https://www.TheEngineeringProjects.com/>The Engineering Projects</a> (TEP). I am a programmer since 2009 before that I just search things, make small projects and now I am sharing my knowledge through this platform.I also work as a freelancer and did many projects related to programming and electrical circuitry. <a href=https://plus.google.com/+SyedZainNasir/>My Google Profile+</a>

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Syed Zain Nasir