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प्रश्न
Calculate the speed of light in a medium whose critical angle is 30° ?
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उत्तर
Speed of light in the medium =`\text { Speed of light in air}/ text { Refractive index of the medium with respet to air}`
`=(3 xx 10^8 m/s)/(1/(sin30°)`
`= (3 xx 10^8 m/s)/2`
`=1.5 xx 10^8m/s`
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संबंधित प्रश्न
The diagram below shows a point source P inside a water container. Four rays A, B, C, D starting from the source P are shown up to the water surface
1) Show in the diagram the path of these rays after striking the water surface.
The Critical Angle for the water-air surface is 48°.
2) Name the phenomenon which the rays B and D exhibit.
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Swarali has got the following observations while doing an experiment. Answer her questions with the help of observations.
Swarali observed that the light bent away from the normal, while travelling from dense medium to rarer medium. When Swarali increased the values of angle of incidence (i), the values of angle of refraction (r) went on increasing. But at a certain angle of incidence, the light rays returned into the dense medium.
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