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Question
State the advantages of potentiometer over voltmeter.
Solution
Advantages of potentiometer over voltmeter:
- The voltmeter is used to measure the terminal P.D. of the cell, while the potentiometer is used to measure the small terminal P.D. as well as the e.m.f. of the cell.
- The accuracy of the potentiometer can be easily increased by increasing the length of the wire.
- A small P.D. can be measured accurately with the help of a potentiometer. The resistance of the voltmeter is high but not infinite to work as an ideal voltmeter.
- The internal resistance of a cell can be measured with the help of a potentiometer.
- The potential difference across the wire is greater than E1 or E2 or E1 + E2.
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Specific resistance of a conductor increase with.
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