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

InterviewSolution

1.	Why is potentiometer preferred over a voltmeter for measuring emf?
Answer» A voltmeter should ideally have an infinite resistance so that it does not draw any current from the circuit. However a voltmeter cannot be designed to have infinite resistance. A potentiometer does not draw any current from the circuit at the null point. Therefore, it gives more accurate measurement. Thus, it acts as an ideal voltmeter.

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