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Question
Calculate the speed of light in a medium whose critical angle is 30° ?
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Solution
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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