ray optics class 12

Question

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For a given incident ray as shown in figure, to under go total internal reflection at the vertical face, the refractive index of slab will be

Answer 1

We know the two conditions for total internal reflection :

1. The ray of light must travel from a denser medium into a rarer medium.

2. The angle of incidence in the denser medium must be greater than the critical angle for that pair of media.

Therefore, the refractive index of slab will be √(3/2)