Physics · 2017
JEE Main · 9 April 2017, Shift 1 · Q16
A uniform wire of length l and radius r has a resistance of 100 Ω. It is recast into a wire of radius r/2. The resistance of new wire will be:
A uniform wire of length $\displaystyle l$ and radius r has a resistance of $\displaystyle 100 \Omega$. It is recast into a wire of radius $\displaystyle \frac{\mathrm{r}}{2}$. The resistance of new wire will be :
Official answer
(1)
$\displaystyle 1600 \Omega$
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JEE Main 2017 Physics question, with the answer from NTA’s final answer key. Where our answers come from.