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Question
In the following figure, show two rays A and B travelling from water to air. If the critical angle for water- air surface is 48°, complete the ray diagram showing the refracted rays for each. State conditions when the ray will suffer total internal reflection.
Solution
The necessary conditions for total internal reflection to occur are
- Light must travel from a denser medium to a rarer medium.
- The angle of incidence must be greater than the critical angle.
In this case, the angle of incidence. ∠ i > 48°
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