Why is a potentiometer preferred over a voltmeter for measuring e… - Vidyadip

Question

Why is a potentiometer preferred over a voltmeter for measuring emf?

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Answer

A voltmeter should have an infinite resistance so that it draws no current from the circuit. A voltmeter, on the other hand, cannot be designed to have infinite resistance. At the null point, a potentiometer draws no current from the circuit. It provides a more accurate measurement. As a result, it serves as an ideal voltmeter.

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