CBSE 2023 · Region 2 · Set 1 · Q4 · 1 mark
A cell of emf E is connected across an external resistance R . When current ' $\displaystyle \mathrm{I}$ ' is drawn from the cell, the potential difference across the electrodes of the cell drops to V . The internal resistance ' r ' of the cell is
Official answer
From CBSE’s own marking scheme for this paper.
(D)
$\displaystyle \left(\frac{\mathrm{E}-\mathrm{V}}{\mathrm{V}}\right) \mathrm{R}$
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CBSE Class 12 Physics past-paper question from the 2023board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.