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Physics · 2025 · 1 mark
CBSE 2025 · Region 1 · Set 2 · Q2
The resistance of a wire of length L and radius r is R. Which one of the following would provide a wire of the same material of resistance R/2?
The resistance of a wire of length L and radius r is R. Which one of the following would provide a wire of the same material of resistance $\displaystyle \frac{R}{2}$?
Official answer
(B)
Using a wire of same radius and half length
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