An experiment is conducted to compare the emf of two cells using a potentiometer. A primary cell and a secondary cell are connected in series through a potentiometer wire of length L = 100 cm. The balancing length for the primary cell is L1 = 40 cm, and for the secondary cell, it is L2 = 60 cm. If the internal resistance of the potentiometer is negligible, calculate the ratio of the emf ( / ) of the two cells.
2/3
4/3
2/5
7/3
Given values:
Length of the potentiometer wire (L) = 100 cm
Balancing length for primary cell (L1) = 40 cm
Balancing length for secondary cell (L2) = 60 cm
The ratio of emf of the two cells ( / ) can be calculated using the formula:
Step 1: Calculate the ratio of emf of the two cells:
The ratio of emf of the primary cell to the secondary cell is 2/3.
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