The critical angle for total internal reflection at the boundary between an unknown substance and air is 24.4°. what is the angle of refraction in the air if light is incident on the boundary at an angle of 20.0°?

Consider the phase change taking place in the picture. you could use all but one statement to describe what is happening here. that is: a) temperature is increasing. b) kinetic energy is increasing. c) the space between the particles remains the same. d) the attractive force between the particles is decreasing.