1. UNIT 3 ~ PHYSICS Lesson P5 ~ The Ray Model of Light

2. THE RAY MODEL OF LIGHT

3. LIGHT AND MATTER
The type of matter in an object determines the amount of light it reflects, absorbs, and transmits

4. Transparent material  allows light to pass through it freely (light is transmitted)
Objects can be seen clearly through the material
Example: Clear windows

5. Translucent material  allows most light rays through but scatters the light (light is transmitted, absorbed, and reflected)
Objects can NOT be seen clearly
Example: Frosted glass in bathroom windows

6. Opaque material  allows NO light to get through (absorbs or reflects all light)
Objects can not be seen at all
Example: Concrete wall

7. Transparent
Translucent
Opaque

9. RAY DIAGRAMS & SHADOWS
The closer the object is to the light source, the larger the shadow it will create.

10. LIGHT CAN BE REFLECTED
In order for something to act as a mirror and reflect an image, it has to be perfectly smooth.

11. THE LAW OF REFLECTION
Light rays hit a mirror and bounce off (reflect off)
The incoming ray is called the incident ray
The outgoing ray is called the reflected ray

12. The incident ray and the reflected ray on either side of a line called the normal
The normal is an imaginary line that is perpendicular to the boundary

13. The angle made by the incident ray and the normal is called the angle of incidence (i)
The angle made by the reflected ray and the normal is called the angle of reflection (r)
(i) is always equal to (r)
This is called the Law of Reflection

14. LIGHT CAN BE REFRACTED
Light bends when it moves into different mediums
Light bends because the speed changes
The angle of refraction is the angle between the refracted ray of light and the normal