Physics · 2025
JEE Main · 4 April 2025, Shift 1 · Q40
A small mirror of mass m is suspended by a massless thread of length l. Then the small angle through which the thread will be deflected when a short…
A small mirror of mass m is suspended by a massless thread of length $\displaystyle l$. Then the small angle through which the thread will be deflected when a short pulse of laser of energy E falls normal on the mirror
( $\displaystyle \mathrm{c}=$ speed of light in vacuum and $\displaystyle g=$ acceleration due to gravity)
Official answer
From NTA’s final answer key for this paper.
(4)
$\displaystyle \theta=\frac{2 E}{m c \sqrt{g l}}$
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JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.