Two cells are compared using a potentiometer. The null lengths are $\ell_1 = 360$ cm for cell 1 and $\ell_2 = 240$ cm for cell 2. The ratio $\varepsilon_1 / \varepsilon_2$ equals:
A3/2
B2/3
C1.0
D3
Answer & Solution
Correct answer: A. 3/2
$\varepsilon_1/\varepsilon_2 = \ell_1/\ell_2 = 360/240 = 3/2 = 1.5$.
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