1. What happens when light hits an object?

2. The Ray Model of Light
To trace the straight-line path that light travels, scientists use an arrow called a ray
A light ray is a line and arrow representing the straight line path of light
A beam is a group of parallel rays.

3. What happens when light hits an object?
The reason we see an object is because the object can do the following with light:
Reflection
Absorption
A bit of both

4. Reflection
Reflection is the process in which light ‘bounces off’ a surface and changes direction
How would you use a ray diagram to illustrate this?

5. Absorption
Absorption is the process in which light energy remains in an object and is converted into heat
Objects appear the colour they are because they absorb all colours of the spectrum except the one our eyes see (it is reflected)
The black ‘E’ below appears black because it absorbs all of the light that hits it (no light hits your eyes) E

6. Absorption/Reflection

7. Transmission
Transmission is the process in which light travels through an object and continues travelling
Different objects transmit different amounts of light
There are 3 ways to describe transmission:
Transparent
Translucent
Opaque

8. Transparent
If light is transmitted directly through an object without any change in direction, the object is transparent
What is an example of a transparent object?

9. Translucent
If light can penetrate an object but it is scattered in many directions, the object is translucent
What is an example of a translucent object?

10. Opaque
If an object absorbs or reflects light only and no light penetrates it, the object is opaque
What is an example of an opaque object?

11. Transparent/Translucent/Opaque