Write an experimental denomstration to show the total internal reflection in water with a laser beam.

Draw a ray diagram to show the total internal reflection.

What is the condition for total internal reflection?

Give some examples of total internal reflection in nature.

What is the technical applications of total internal reflection?

Write one chemical reaction to show the amphoteric nature of water.

A LASER is a source- of very intense, monochromatic, and unidirectional beam of light. These properties of a laser light can be exploited to measure long distances. The distance of the Moon from the Earth has been already determined very precisely using a laser as a source 'of light. A laser light beamed at the Moon takes 2.56 s to return after reflection at the Moon’s surface. How much is the radius of the lunar orbit around the Earth?