Reflection: What is it?Reflection occurs when light bounces off an object.Reflection allow our eyes to see the world around us!

Laws of ReflectionThe angle of incidence is equal to the angle of

reflectionThe incident ray, the reflected ray, and the

normal line all lie in the same plane.Paths of light rays are reversible.

Ray Diagrams

A “light ray” is a line and arrow representing the direction and straight-line path of light.

Combinations of light rays can be used to construct a “ray diagram”.

Such ray diagrams describe the behaviour of light in a certain circumstance (e.g. Being emitted from a light bulb, reflected off a mirror, or refracted into water)

Reflection: surfacesSmooth surfaces create a mirror-like effect called

“Spectacular reflection”:

Reflection off rough surfacesDiffuse reflection results from the reflection

of light off an irregular surface.

Reflection: surfacesReflection is how we see the world

Example of laser: can’t see it until use dust!Examine light ray diagrams of smooth and rough

surfaces:All individual incident rays will still follow the laws of

reflection

Images in MirrorsThe image you see in the mirror isn’t real.... It’s “VIRTUAL”!How far away does the “virtual” you appear to

be compared to the real you and the mirror?Try creating a light ray diagram of yourself

looking in the mirror.