Question

In a potentiometer experiment, the balancing length is 8 m, when the two cells E1 and E2, are joined in series. When the two cells are connected in opposition the balancing length is 4 m. The ratio of the e.m.f. of two cells (E1/E2,) is (A) 1:2 (B) 2:1 (C) 1:3 (D) 3:1
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Answer 1

Answer:

Explanation:

In a potentiometer experiment, the balancing length is 8 m, when the two cells E1 and E2, are joined in series. When the two cells are connected in opposition the balancing length is 4 m. The ratio of the e.m.f. of two cells (E1/E2,) is (A) 1:2 (B) 2:1 (C) 1:3 (D) 3:1

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Answer 2

Given:

The balancing length is $8m$,when the two cells $E_{1}$and $E_{2}$are joined in series. When the two cells are connected in opposition the balancing length is $4m$.

To find:

The ratio of the two cells.

Explanation:

By using the relation,

$\frac{E_{1}}{E_{2}} =\frac{l_{1}+l_{2}}{l_{1}-l_{2}}$

$=\frac{(8+4)}{(8-4)}$

$=\frac{12}{4}$

$=\frac{3}{1}$

Answer:

Therefore, the ratio of the two cells in 3:1.