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What is the speed of light in a glass if you know that the speed of light in a vacuum is c=3.0x108 m/s and the refractive index of the glass is 1.52?

User JD Frias
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1 Answer

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In order to calculate the speed of light in the glass, we can use the formula below:


n=(c)/(v)

Where n is the index of refraction, c is the speed of light in a vacuum and v is the speed of light in the corresponding index of refraction.

So we have:


\begin{gathered} 1.52=(3\cdot10^8)/(v)\\ \\ v=(3.10^8)/(1.52)\\ \\ v=1.97\cdot10^8\text{ m/s} \end{gathered}

Therefore the speed of light in this glass is 1.97 * 10^8 m/s.

User Superdunck
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