Potentiometer measures the potential difference more accurately than a voltmeter because |
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a) |
It has a wire of high resistance |
b) |
It has a wire of low resistance |
c) |
It does not draw current from external circuit |
d) |
It draws a heavy current from external circuit |
Potentiometer measures the potential difference more accurately than a voltmeter because |
|||
a) |
It has a wire of high resistance |
b) |
It has a wire of low resistance |
c) |
It does not draw current from external circuit |
d) |
It draws a heavy current from external circuit |
(c) When we measure the emf of a cell by the potentiometer then no current flows in the circuit in zero-deflection condition , cell is in open circuit. Thus, in this condition the actual value of a cell is found. In this way, potentiometer is equivalent to an ideal voltmeter of infinite resistance. |