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Question
The refractive indices of glass and water with respect to air are 3/2 and 4/3 respectively. If speed of light in glass is 2 x 108 m/s, find the speed of light in water.
Solution
Given: ng = 3/2 and nw = 4/3
`nw=`
`4/3=(3 xx 10^8)/`
Speed of light in water = `(3xx3xx10^8)/4`
Speed of light in water = 2.25 x 108 m/s
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