A ray of light passes from glass into air. The angle of refraction will be:

Explain with the help of a labeled ray diagram, why a pencil partly immersed in water appears to be bent at the water surface. State whether the bending of pencil will increase or decrease if water is replaced by another liquid which is optically more dense than water. Give reason for your answer.

Light travelling from a denser medium to a rarer medium along a normal to the boundary:

A ray of light travelling in air goes into water. The angle of refraction will be:

The speed of light in air is: