Question

green light (520 nm) enters glass with n = 1.52. what is speed of light in the glass? (answer is * 10^8 m/s. just fill in the number in the blank, not the power.)

Explanation:

Step1: Recall the formula for the speed of light in a medium

The formula is $v=\frac{c}{n}$, where $c = 3\times10^{8}\text{ m/s}$ is the speed of light in a vacuum and $n$ is the refractive - index of the medium.

Step2: Substitute the given values

Given $n = 1.52$ and $c = 3\times10^{8}\text{ m/s}$, then $v=\frac{3\times10^{8}}{1.52}\text{ m/s}$.
Calculating $\frac{3}{1.52}\approx1.97$.

Answer:

1.97