Physics · 2021
JEE Main · 22 July 2021, Shift 2 · Q3
A ray of light passes from a denser medium to a rarer medium at an angle of incidence i. The reflected and refracted rays make an angle of 90° with…
A ray of light passes from a denser medium to a rarer medium at an angle of incidence $\displaystyle i$. The reflected and refracted rays make an angle of $\displaystyle 90$° with each other. The angle of reflection and refraction are respectively r and r'. The critical angle is given by :
Official answer
(3)
$\displaystyle \sin ^{-1}(\tan r)$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.