MCQ
Two cells of emf $E_1$ and $E_2\left(E_1 > E_2\right)$ are connected individually to a potentiometer and their corresponding balancing length are $625 \,cm$ and $500 \,cm$, then the ratio $\frac{E_1}{E_2}$ is ...........
  • $5: 4$
  • B
    $3: 1$
  • C
    $5: 1$
  • D
    $4: 5$

Answer

Correct option: A.
$5: 4$
a
(a)

$E_1=k l_1$ $\quad k$ is potential gradient

$E_2=k l_2$

$\frac{E_1}{E_2}=\frac{l_1}{l_2}=\frac{625}{500}=\frac{25}{20}=\frac{5}{4}$

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