Physics · 2021
JEE Main · 31 August 2021, Shift 1 · Q16
A uniform heavy rod of weight 10 kg ms^-2, cross-sectional area 100 cm^2 and length 20 cm is hanging from a fixed support. Young modulus of the…
A uniform heavy rod of weight $\displaystyle 10 \mathrm{~kg} \mathrm{~ms}^{-2}$, cross-sectional area $\displaystyle 100 \mathrm{~cm}^2$ and length $\displaystyle 20$ cm is hanging from a fixed support. Young modulus of the material of the rod is $\displaystyle 2 \times 10^{11} \mathrm{Nm}^{-2}$. Neglecting the lateral contraction, find the elongation of rod due to its own weight :
Official answer
(2)
$\displaystyle 5 \times 10^{-10} \mathrm{~m}$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.