Light and Heat

Refraction of light

Light travels in a straight line but when it enters another medium it would be seen to bend.

How does a lens work?

A lens is a plastic or glass, which refracts light to form an image. When we look through a lens it will seemed like it was distorted. This because light undergoes refraction as it travels from air to glass and back to air again. Lenses are usually used to magnify objects. The examples are magnifying glass, microscopes, spectacles, cameras and telescopes.

Dispersion of light through a prism

White light is actually made up of different colours. We can prove this by shining white light to a prism, a a transparent plastic or glass object with smooth surfaces and can refract light. It occurs because, light travels at different speeds and the different colours refract at different angles as they pass through a prism.

Dispersion of light through water droplets

Water droplets can also act like a prism. The water droplets refract on sunlight.

Transfer of Heat

Conduction: Heat is transferred from one object to another. The example is, from the heat of boiling water to a spoon.

Convection: The transfer of heat from one region to another by the movements of fluids. The example is, from cold water to hot water.

Radiation: It is the release of heat from the surface