Physics
General
Easy

Question

A potentiometer is preferred over a voltmeter to measure the emf of a cell because....

  1. The material of the potentiometer wire has a low temperature coefficient of resistance.
  2. emf measured by potentiometer is more accurate because the cell is open-circuit.
  3. potential gradients can be varied in a potentiometer using a rheostat.
  4. 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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