The method of comparing two emfs of a cell

r=1

E=24

V=15

r=12

Dear student 

Potentiometer is a device used to compare the e.m.f. (electromotive force) of two cells, to measure the internal resistance of a cell, and potential difference across a resistor. It consists of a long wire of uniform cross-sectional area and of 10 m in length.

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