Question

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

Answer 1

The ray of light will bend towards the normal as it enters from an optically rarer to a denser medium and it's speed decreases.

Answer 2

Hey!

The light ray bends towards the normal.

A light ray travelling from a rarer to a denser medium always bends towards the normal as its speed decreases.
 
In this case, water is more denser than air. Therefore, the ray bends towards the normal because its speed reduces when it travels from the rarer medium (air) to the denser medium (water).