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प्रश्न
If the absolute refractive index of glass and water are 3/2 and 4/3 respectively, what is the refractive index of glass with respect to water?
उत्तर
If v1 is the velocity of light in vacuum, v2 is the velocity of light in glass and v3 is the velocity of light in water then, absolute refractive index of glass, i.e., a refractive index of glass with respect to vacuum,
`"n"_"g" = "v"_1/"v"_2 = 3/2` ...(i)
Absolute refractive index of water ,i.e., refractive index of water with respect to vacuum,
`"n"_"w" = "v"_1/"v"_3 = 4/3` ...(ii)
∴ Refractive index of glass with respect to water,
gnw = `"v"_3/"v"_2`
`= "v"_1/"v"_2 xx "v"_3/"v"_1` ....(Multiplying and dividing R.H.S. of equation by v1)
`= 3/2 xx 3/4` ...[From equations (i) and (ii)]
`= 9/8`
The refractive index of glass with respect to water is `9/8`
संबंधित प्रश्न
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Refractive index | Material medium | Refractive index |
| Air | 1.0003 | Canada Balsam | 1.53 |
| Ice | 1.31 | – | – |
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1.46 | Dense flint glass |
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| A | 1.33 |
| B | 1.44 |
| C | 1.52 |
| D | 1.65 |
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- (A) The speed of light in glass is 2 × 108 m/s and is water is 2.25 × 108 m/s.
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OR
(B) The absolute refractive indices of glass and water are 4/3 and 3/2, respectively. If the speed of light in glass is 2 × 108 m/s, calculate the speed of light in (i) vacuum (ii) water.
