What is the speed of light in a material that has an index of refraction of 2.0?
A) $1.5 \times 10^{8} \mathrm{~m} / \mathrm{s}$
B) $2.0 \times 10^{8}\mathrm{~m} / \mathrm{s}$
C) $5.0 \times 10^{8} \mathrm{~m} / \mathrm{s}$
D) $6.0 \times 10^{8} \mathrm{~m} / \mathrm{s}$
E) No such index can exist.

Question

Quizplus · Accepted Answer

The speed of light in a material is given by $v = \frac{c}{n}$, where $c$ is the speed of light in vacuum ($3.0 \times 10^8 \, \text{m/s}$) and $n$ is the index of refraction. For $n = 2.0$, $v = \frac{3.0 \times 10^8}{2} = 1.5 \times 10^8 \, \text{m/s}$.

What Is the Speed of Light in a Material That 1.5×108 m/s1.5 \times 10^{8} \mathrm{~m} / \mathrm{s}1.5×108 m/s

What Is the Speed of Light in a Material That $1.5 \times 10^{8} \mathrm{~m} / \mathrm{s}$