Physics · 2015
NEET 2015 · 25 July · Code C · Q34
A potentiometer wire of length L and a resistance r are connected in series with a battery of e.m.f. E_0 and a resistance r_1. An unknown e.m.f. E is…
A potentiometer wire of length $\displaystyle L$ and a resistance $\displaystyle r$ are connected in series with a battery of e.m.f. $\displaystyle \mathrm{E}_0$ and a resistance $\displaystyle r_1$. An unknown e.m.f. E is balanced at a length $\displaystyle l$ of the potentiometer wire. The e.m.f. E will be given by :
Official answer
From NTA’s final answer key for this paper.
(4)
$\displaystyle \frac{\mathrm{E}_0 \mathrm{r}}{\left(\mathrm{r}+\mathrm{r}_1\right)} \cdot \frac{l}{\mathrm{L}}$
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NEET (UG) 2015 Physics question, with the answer from NTA’s final answer key. Where our answers come from.