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Question
Observe the given figure and name the following.
| Ray AB | |
| Ray NM | |
| Ray MD | |
| ∠ r |
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Solution
| Ray AB | Incident ray |
| Ray NM | Refracted ray |
| Ray MD | Emergent ray |
| ∠ r | Angle of refraction |
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| Column I | Column II | ||
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