Reflection of light
normal: at right angles to the mirror surface where the light rays strike at it.
i: angle of incidence r: angle of reflection
Law of reflection:
The angle of incidence = the angle of reflection
An image on a mirror is a virtual image. It appears to be the same distance behind the mirror as it is infront.
Refraction of light
When a light ray travels from air into glass it is bent towards the normal and when a light ray travels back out of glass into air, it is bent away from the normal.
Law of refraction:
refractive index, n = sin i / sin r OR 1/ sin c
Critical angle, c: the angle at which the reflection travels at a 90degree angle to the normal.
Refraction is used in optical fibres. Light can be diffracted.
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