A student observes that water waves in a ripple tank change direction as they pass over a submerged glass plate that makes the water shallower. This change in direction is primarily caused by a change in the wave's:

A ray of light is incident on a plane mirror at an angle of $25^\circ$ to the normal. What is the total angle between the incident ray and the reflected ray?

A light ray travels from a liquid with a refractive index of $n_1 = 1.40$ into air ($n_2 = 1.00$). If the angle of refraction in the air is , what is the value of for the incident ray in the liquid?

Calculate the speed of light in a diamond that has a refractive index of $n = 2.42$. (Take the speed of light in a vacuum to be $c = 3.00 \times 10^8\ \text{m}\ \text{s}^{-1}$)

A light ray travels from glass (${n = 1.50}$) into water (${n = 1.33}$). Which of the following best describes its path as it crosses the boundary?