If the index of refraction of a material is 2, this means that light travels
A) 2 times as fast in air as it does in vacuum.
B) 2 times as fast in vacuum as it does in the material.
C) 2 times as fast in the material as it does in air.
D) 1/2 as fast in air as it does in the material.
E) 2 times as fast in the material than it does in vacuum.

Question

Quizplus · Accepted Answer

The index of refraction (n) is defined as the speed of light in vacuum divided by the speed of light in the material. Therefore, if n = 2, light travels 2 times as fast in vacuum as it does in the material.

If the Index of Refraction of a Material Is 2