What is Potentiometer ?
Potentiometer is a three terminal electronics component that is used to vary the length of resistance and to divide voltage with the required amount of output .They are used in many applications like tunning radio , increasing or decrease volume , to dim a LED , they can be used as sensors in many applications .
Principle of Potentiometer
The main principle of potentiometer is its resistance is change due to length of conductor inside it . If we change the wiper of potentiometer we are actually changing length of conductor . Hence one wiper divides the length of resistance into two part and hence voltage is divided according to the length of coil
HOW TO USE POTENTIOMETER
You can use potentiometer either to make a variable resistor ( as a varistor ) or as a potential divider circuit (to measure voltage ) .In variable resistor form (to make varistor ) we connect middle pin with one of another pin and this joint pin is connect to circuit in series with another remaining pin . As shown in animated circuit diagram below current is changing as resistance changed.
And to make it potential divider we connect all three terminal in such a way that first cornor pins go to VCC and ground and from middle pin we get required voltage . As shown in figure below potentiometer changes the voltage between the circuit .
That's all about potentiometer . So it depends whether you are measuring voltage or measuring current making it as your choice . Cheers!