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The refractive index of water with respect to vacuum is 4/3 and refractive index of vacuum with respect to glass is 2/3. If the speed of light in glass is 2x 108m/s, find the speed of light in i) Vacuum ii) water

User Shanikqua
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1 Answer

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As we know that


\mu = (speed of light in air)/(speed of light in medium)

now for the first part we know that

refractive index of vacuum with respect to glass is 2/3

speed of light in glass is
2 * 10^8 m/s

now we will have


(2)/(3) = (2* 10^8)/(c)


c = 3 * 10^8 m/s

Part b)

Now similarly we can say


\mu = (speed of light in air)/(speed of light in medium)

here refractive index of water with respect to vacuum is 4/3


(4)/(3) = (3 * 10^8)/(v)

now we will have


v = 2.25 * 10^8 m/s

User MartinMlima
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