Question

Why potentiometer superior to voltmeter?

Answer 1

Both potentiometer & Voltmeter are used to measure potential difference. However, when using a voltmeter there is a voltage drop within the voltmeter, so the measurements will not be accurate. Potentiometer in turn uses null point ( balance between two sides), the potentiometer gives accurate measurement when the galvanometer shows zero deflection. Hence, there is no voltage drop anywhere and hence gives the accurate value of the emf ( voltage).