We know that sunlight shines onto every object we see. Some of the light bounces off the object again. We say it is ‘reflected’. We can only see objects when they reflect light. Most objects have no light source of their own. We see them because they reflect the Sun’s light.
Every substance reflects some light. Shiny, smooth surfaces, such as metals, are the best reflectors of light. A mirror, made from a sheet of glass with a thin layer of silver or aluminium on the back, reflects light almost perfectly. However, a mirror image can be misleading. You appear the wrong way round in an ordinary mirror — left appears right and vice versa, and your reflection may be very distorted in a curved mirror.
Mirror images
Letters held in front of a mirror appear the wrong way round in the reflection. We say they are ‘laterally inverted’. But if a second mirror is added, at right angles to the first, the image is turned round again.