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Question
The velocity of light in diamond is 121000 kms-1. What is its refractive index?
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Solution
Speed of light in diamond = 121,000 km/s
= 121 × 106 m/s
Refractive index of diamond = `"Speed of light in air"/"speed of light in diamond"`
= `(3xx10^8)/(121xx10^6"m/s")`
= 2.48
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While tracing the path of a ray of light passing through a rectangular glass slab a student tabulated his observations as given below:
|
S.NO. |
∠i |
∠r |
∠e |
|
I |
60° |
40° |
61° |
|
II |
50° |
36° |
51° |
|
III |
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28° |
39° |
|
IV |
30° |
20° |
31° |
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(D) IV
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