Light travels through a material at a speed of 2.1 x 108 m/s. What is the index of

refraction for the material?

Refractive index is 1.43

Explanation:

We are given;

The speed of light through a material as 2.1 * 10^8 m/s

We are required to determine the refractive index of the material.

We need to know refractive index may be given by the formula; Refractive index = Speed of light in air : speed of light in a material

The speed of light in air is 3.0 * 10^8 m/s

Therefore;

Refractive index = 3.0 * 10^8 m/s : 2.1 * 10^8 m/s

= 1.4286

= 1.43

Thus, the refractive index of the material is 1.43