# Homework Help: Light travelling through differing mediums

1. Aug 9, 2011

### fmdk

If light traveling in water hits an interface with air at angle x, what is the angle it will make when traveling in air?

what factors do i need to consider for this apart from:

different lights travel at different speeds

different mediums will affect angle of incidence

2. Aug 9, 2011

### CompuChip

The thing you're looking for is probably called "Snell's law" (named after a Dutch scientist with the fancy Latin name Snellius):
$$\frac{\sin \theta_1}{\sin \theta_2} = \frac{c_1}{c_2} = \frac{n_2}{n_1}$$
where $n_i = c / c_i$ and $c_i$ is the speed of light in medium i (and c in vacuum).