Question

How would you use a piece of Polaroid to look at the bottom of a pond if reflections are a problem? Would it be any different if the pond is covered with a layer of oil?

Hint: (Refractive index of water = 1.33 and of oil = 1.5). Show calculations.

Answer 1

reflections are polarized in the plane lying in the surface of the pond. Same issue as reflections off roads or automobiles.