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## Class 12 Physics (India)

### Course: Class 12 Physics (India)>Unit 3

Lesson 12: Potentiometers

# Potentiometer principle (logic) & working

Let's explore, logically, the working principle of a slide-wire potentiometer. A potentiometer can measure voltages, with higher accuracy than a voltmeter, without drawing a current from the main circuit. Created by Mahesh Shenoy.

## Want to join the conversation?

• About the last question, a second case where the galvanometer can never be 0, is it when the source cell's terminals are connected to the driver cell's opposite terminals?
• In reference to that last question, a second scenario where galvanometer will show no deflection is it because of the internal resistance of the battery. Because practically even batteries have internal resistance and thus the value is not equal to the emf but something less than that. And that practical value might be less than the terminal voltage of that resistance( in this case the bulb).
• How do you make sure that current doesn't flow through the wire were galvanometer is not connected?
(1 vote)
• It can't flow that way since it would violate Kirchhoff's junction rule: There is current flowing in, but no current flowing out.