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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
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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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