Hi guys,

I do not have a whole lot of knowledge concerning electronics so I am turning to the forums for information.
In my circuit I want to control a servo motor. But I only want to power this servo when I am using it.
Here comes the transistor in the picture. With a USB supplying 5V to the collector of the transistor, and a raspberry Pi supplying 2.5V to the Base. I thought the Emitter would pass through about 5V, but it is only passing 2V.

I need to power my server with roughly 5V and be able to control the power to this circuit with my Raspberry Pi.

Is this the right approach? What am I doing wrong

Thanks in advance for your help