Q 12-03-144JEE MainJEE Main 2023 (6 Apr, Shift 1)Easy
The length of a metallic wire is increased by $20\%$ and its area of cross-section is reduced by $4\%$. The percentage change in resistance of the metallic wire is ______.
Numerical value type. Enter your answer.
Answer: 25
$R\propto\dfrac lA$: $\dfrac{1.2}{0.96}=1.25$, an increase of $25\%$.
Solution by Sreeraj P, M.Sc Physics