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प्रश्न
- Explain why the refractive index of any material with respect to air is always greater 1.
- In the figure below a light ray travels from air into the semi-circular plastic block. Give a reason why the ray does not deviate at the semi-circular boundary of the plastic block.
- Complete the ray diagram of the above scenario when the light ray comes out of the plastic block from the top flat end.
उत्तर
- The refractive index of a medium with respect to air is given by `"speed of light in the air"/"speed of light in the medium"`. Since the speed of light in the medium is always less than the speed of light in air, hence the above ratio is always greater than 1.
- The ray of light is undergoing normal incidence at the air-plastic block interface. And for normal incidence, there is no deviation.
(Credit arrows, refracted ray moving away from normal)
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संबंधित प्रश्न
The velocity of light in a medium is 1.5 x 108 m/s. What is the refractive index of the medium with respect to air, if the velocity in air is 3 x 108 m/s?
Fill in the following blank with a suitable word:
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The speed of light in substance X is 1.25 × 108 m/s and that in air is 3 × 108 m/s. The refractive index of this substance will be:
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The refractive index of air with respect to glass is 2/3 and the refractive index of water with respect to air is 4/3. If the speed of light in glass is 2 × 108 m/s, find the speed of light in (a) air, (b) water.
n = _______. This law is also called as Snell’s law.
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