Question

when a light ray makes90° while entering a glass slab form air, it...​

Answer 1

Answer:

Explanation: Refraction is the process of bending of light as it moves from one medium to another. When light ray from air in incident to a glass slab at any angle except 90 degrees, refraction occurs and the light ray bends towards the normal.

Explanation:

Answer 2

Answer:

because of reflection.

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