The sketch given below shows a light ray moving from glass into air, at 30º to the normal.

 

Below a light ray is shown moving from water into a rectangular block of air (inside a thin-walled plastic box), at 40º to the normal. On a sheet of notebook paper, show your partner the actual path the light would take inside the air.

 

Light from the air passes through plates of glass and plastic below. The speeds of light in the different materials is shown (these different speeds are often implied by the "Index of refraction" of the material). On a sheet of notebook paper, show your partner a rough sketch showing an appropriate path through the system of four plates.