Unit 1D / 3F - Light

A light source generates light. An example would be a lamp or light bulb, or the Sun. The Moon isn't a light source, it reflects light produced by the sun.

Opaque materials do not let light pass through them. They absorb certain colours and reflect others. For example a blue surface reflects blue light and absorbs the other colours. A black surface abosorbs all colours and a white surface reflects every colour.

A shadow is caused by an object blocking light that falls onto a surface.

Some mateials are very reflective. They reflect the light that falls on to them but because they are very flat the light forms a clear opposite image.