Why do we prefer a potentiometer to measure emf of a cell rather than a voltmeter ?
Text Solution
Verified by Experts
At null point, a potentiometer does not draw any current from the cell whose emf is to be determined, whereas a voltmeter, always draws some little current. Therefore, emf measured by voltmeter is slightly less than actual value of emf of the cell.
Topper's Solved these Questions
CURRENT ELECTRICITY
PRADEEP|Exercise Conceptual Problems|3 Videos
CURRENT ELECTRICITY
PRADEEP|Exercise Very short Q/A|7 Videos
COMMUNICATION SYSTEMS
PRADEEP|Exercise MODEL TEST PAPER-2|9 Videos
DUAL NATURE OF RADIATION AND MATTER
PRADEEP|Exercise Exercise|191 Videos
Similar Questions
Explore conceptually related problems
Why do we prefer potentiometer with a longer bridge wire?
In a potentiometer experiment, to measure the e.m.f. of a cell, the potentiometer consists of six wires each of length 100 cm. The null point is obtained on the third wire. If we want to shift the null point to the 5th wire, then we should
Would you prefer a vlotmeter or a potentiomer to measure the emf of a battery?
In a potentiometer experiment for measuring the emf of a cell the null point is at 240 cm when we have a 400 omega resistor in series with the cell and galvanometer. If the series resistance is reduced to half, the null point will be at
Assertion A potentiometer is preferred over that of a voltmeter for measurement of emf of a cell Reason potentiometer does not draw any current from the cell.
Volymeter can not be used to measure emf to a cell potentiometer can be used to measure emf of a cell because
PRADEEP-CURRENT ELECTRICITY-Problems for Practice (B)
