Physics
General
Easy
Question
A potentiometer is preferred over a voltmeter to measure the emf of a cell because....
- The material of the potentiometer wire has a low temperature coefficient of resistance.
- emf measured by potentiometer is more accurate because the cell is open-circuit.
- potential gradients can be varied in a potentiometer using a rheostat.
- Potentiometer is more sensitive than voltmeter.
The correct answer is: emf measured by potentiometer is more accurate because the cell is open-circuit.
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