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Question
Calculate the velocity of light in a glass block of refractive index 1.5. (Velocity of light in air = 3 × 108 m/s)

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Solution

`"V"_"air"/"V"_"glass"=mu_"glass"/mu_"air"`
or Vglass = `3xx10^8xx1/1.5`
= 2 × 108 m/s.
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