Physics · 2021
JEE Main · 17 March 2021, Shift 2 · Q2
Two cells of emf 2E and E with internal resistance r_1 and r_2 respectively are connected in series to an external resistor R (see figure). The value…
Two cells of emf 2E and E with internal resistance $\displaystyle r_1$ and $\displaystyle r_2$ respectively are connected in series to an external resistor R (see figure). The value of R, at which the potential difference across the terminals of the first cell becomes zero is
Official answer
(1)
$\displaystyle \frac{r_1}{2}-r_2$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.