What is reflection?

What do you mean by polarisation by reflection?

If the angle of elevation of a cloud from a point h metre above the lake is alpha and the angle of depression of its reflection in the lake is beta , prove that the height of the cloud above the lake is (h(tan beta+tan alpha))/(tan beta- tan alpha)

Establish Brewster's Law regarding polarisation of light by reflection.

The angle between an incident ray and the mirror is 40°. what is the angle of reflection?

Draw the ray diagram to show the reflection by a plane reflecting surface.

Explain reflection of light on the basis of Huygen's theory.

Give two practical applications of reflection of sound waves.