MCQ
A potentiometer has uniform potential gradient across it. Two cells connected in series (i) to support each other and (ii) to oppose each other are balanced over $6 \mathrm{~m}$ and $2 \mathrm{~m}$ respectively on the potentiometer wire. The e.m.f.'s of the cells are in the ratio of
  • A
    $1: 2$
  • B
    $1: 1$
  • C
    $3: 1$
  • $2: 1$

Answer

Correct option: D.
$2: 1$
(d) $\frac{E_1}{E_2}=\frac{l_1+l_2}{l_1-l_2}=\frac{(6+2)}{(6-2)}=\frac{2}{1}$

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