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Light waves and the rules of reflection

To see an object light has to reflect off the object. Light reflects of all objects and looks different due to how the light reflects of it.
light reflects of rough surfaces differently depending if the surface is rough or smooth.

reflection

Light hits a mirror and bounces off it. This process is called reflection. A incident ray is a ray that of light that hits an object, in this case a mirror. A ray of light that bounces off the mirror is called the reflected ray. There are three rules of reflection:

Diagram

Rule 1: The angle of incidence ray is always the same size as the angle of reflection. (0i = 0r)

The angles are always measured from the ray to the normal line. The normal line is a line at right angles to the mirror.

Make sure that you don't measure the ray from the mirror, you have to measure the rays angle from the incidence ray otherwise you'll get the wrong answer.

Plane (flat) mirrors produce virtual images. This means that the images are not real, they don’t exist. We can see these images because our brains think that they exist.

Diagram

The rays of light reflect off the mirror (obeying rule 1), back into the eye. The brain thinks that light only travels in straight lines, so tracks the lines back to the point behind the mirror. This point is the virtual image. It doesn’t really exist, but the brain thinks it does.

Here are the other rules of reflection:

Rule 2: The image is always the same distance behind the mirror as the object is in front.

Rule 3: The image is always;

- The same size as the object.

- Laterally inverted (left becomes right and right becomes left), which is why writing is back to front in a mirror.

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