Question
State the underlying principle of a potentiometer. Write two factors by which current sensitivity of a potentiometer can be increased. Why is a potentiometer preferred over a voltmeter for measuring the emf of a cell?
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Answer
Principle: The potential drop, across a part of a length l of a uniform wire of length L (L>l), is proportional to the length l.
Two factors:
Two factors:
- Increasing the length L of the wire.
- Connecting a suitable resistance, R, in series with the potentiometer wire.
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