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Question
When a ray of light travels from air to glass slab and strikes the surface of separation at 90°, then it …………….
(a) bends towards normal
(b) bends away from normal
(c) passes unbent
(d) passes in zigzag way
Solution
(c) passes unbent
In this case, the angle of incidence (i) is zero and so also the angle of refraction.
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