Question

What is the speed of light in Crown glass? answer:______m/s

Answer 1

197,368,421.1 m/s ≈ 1.97 x 10⁸ m/s

Step-by-step explanation

The speed of light in a medium with an index of refraction n is given by,

`v=(c)/(n)`

Where c is the speed of light in a vacuum, which is 3 x 10⁸ m/s.

In this case, we have to find the speed of light in Crown glass, whose index of refraction is 1.52 at 20°C. So, the speed of light in this medium is,

`v=(3\cdot10^8m/s)/(1.52)=197,368,421.1m/s\approx1.97\cdot10^8m/s`

Hence, the speed of light in Crown glass is 197,368,421.1 m/s ≈ 1.97 x 10⁸ m/s.