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Question
Trace a ray of light incident at 30° on a surface if travelling from air to glass. What is the angle of refraction in this case? (R.I. for glass = 3/2).
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Solution
aμg = `sin"i"/sin"r"`
∴ `3/2=(sin30°)/sin"r"`
∴ Sin r = `2/3xxsin30°`
But sin 30° = `1/2`
∴ sin r = `2/3xx1/2`
= `1/3`
∴ sin r = 0.3334
∴ sin r = 19°30′.
Angle of refraction for air to glass = 19°30′.
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4) What are the rays AB and CD in the figure called?
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|
S.NO. |
∠i |
∠r |
∠e |
|
I |
60° |
40° |
61° |
|
II |
50° |
36° |
51° |
|
III |
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39° |
|
IV |
30° |
20° |
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