Physics · 2021
JEE Main · 26 February 2021, Shift 2 · Q15
The length of metallic wire is l_1 when tension in it is T_1. It is l_2 when the tension is T_2. The original length of the wire will be:
The length of metallic wire is $\displaystyle l_1$ when tension in it is $\displaystyle \mathrm{T}_1$. It is $\displaystyle l_2$ when the tension is $\displaystyle \mathrm{T}_2$. The original length of the wire will be :
Official answer
(4)
$\displaystyle \frac{\mathrm{T}_2 l_1-\mathrm{T}_1 l_2}{\mathrm{~T}_2-\mathrm{T}_1}$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.