Question

how should a ray of light be incident on a rectangular glass slap so that is comes out from the opposite side of the slap without being displace

Answer 1

the ray when passes from refracting medium the angle between the incident ray and refracted ray is more

Answer 2

$\huge\mathfrak\red{Answer :}$

$\textbf{Perpendicular means at 90°.}$

$\underline{Reason :}$

The ray of light should be 90° to the glass slab... So, that it comes out from the the opposite face of the glass slab without being displaced....

This happens because when we take angle of incident = 90°. As it fails the Snell's law....

i.e.

$\dfrac{sin \:i}{sin \:r}$ = $\dfrac{\mu\:1}{\mu\:2}$

Due this it comes out without deviation from the opposite side of the glass slab...

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