CBSE 2025 · Region 1 · Set 1 · Q2 · 1 mark
Two wires P and Q are made of the same material. The wire Q has twice the diameter and half the length as that of wire $\displaystyle P$. If the resistance of wire $\displaystyle P$ is $\displaystyle R$, the resistance of the wire $\displaystyle Q$ will be
Official answer
From CBSE’s own marking scheme for this paper.
(C)
$\displaystyle \frac{R}{8}$
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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.