CBSE 2025 · Region 2 · Set 2 · Q2 · 1 mark
A battery of e. m. f. $\displaystyle 12$ V and internal resistance $\displaystyle 0.5 \Omega$ is connected to a $\displaystyle 9.5 \Omega$ resistor through a key. The ratio of potential difference between the two terminals of the battery, when the key is open to that when the key is closed, is
Official answer
From CBSE’s own marking scheme for this paper.
(A)
$\displaystyle 1.05$
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CBSE Class 12 Physics past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.