A ray of light travelling in air is incident on a parallel-sided glass slab (or rectangular glass slab). Draw a ray-diagram indicating the change in its path in glass.

A beam of light travelling in air is incident on water. Draw a ray-diagram indicating the change in its path in water.

A ray of light travelling in water emerges into air. Draw a ray-diagram indicating the change in its path.

A ray of light travelling in glass emerges into air. State whether it will bend towards the normal or away from the normal.

A ray of light travelling in air enters obliquely into water. Does the ray of light bend towards the normal or away from the normal? Why?