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Question
The refractive indices of water and diamond are `4/3` and 2.42 respectively. Find the speed of light in water and diamond. (c = 3x108 m/s)
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Solution
`""^amu_w = 4/3`
`""^amu_d =2.42`
`""^amu_w = 4/3 = V_a/V_w`
`:. V_w = (3 xx10^8)/(4/3) = 3 xx 10^8 xx 3/4 = 2.25 xx 10^8` m/c
`""^amu_d = 2.42 = V_a/V_d = (3xx10^8)/V_d`
`V_d = (3xx10^8)/2.42 = 1.23 xx 10^8` m/s
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