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प्रश्न
Trace a ray of light incident at 30° on a surface if travelling from glass to air. What is the angle of refraction in this case? (R.I. for glass = 3/2).
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उत्तर
For a ray of light from glass to air R.I. is denoted as gμa.
`""_"g"mu_"a"=1/(""_"a"mu_"g")`
∴ `sin"i"/sin"r′"=1/(""_"a"mu_"g")`
sin r′ = aμg × sin i
and aμg = `3/2`
∴ sin r′ = `3/2xx1/2`
= `3/4`
= 0.7500
∴ r′ = 48°36′
Angle of refraction for glass to air = 48°36′.
संबंधित प्रश्न
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Fig 4.31 below shows a light ray of single colour incident normally on two prisms A and B. In each case draw the path of the ray of light as it enters and emerges out of the prism. Mark the angle wherever necessary.
Rahim recorded the following sets of observations while tracing the path of a ray of light passing through a rectangular glass slab for different angles of incidence.
|
S. No. |
Angle of incidence |
Angle of refraction |
Angle of emergence |
|
I |
45° |
41° |
45° |
|
II |
40° |
38° |
38° |
|
III |
45° |
41° |
40° |
|
IV |
41° |
45° |
41° |
The correct observation is recorded at serial number:
(1) I
(2) II
(3) III
(4) IV
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(ii) what is the XX' called?
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