Memory Anchor:

• Super Challenge:

  Stretch:

  Challenge:

Key Questions:

1. What three things can happen to a wave when it encounters a material?
   • When a wave encounters a material it is either: reflected, absorbed or transmitted.
2. How do light waves travel?
   • Light (waves) travels in straight lines. We use rays to show this.
3. What is the law of reflection off a plane surface?
   • When a wave is reflected from an object like a mirror, the angle of reflection equals the angle of incidence.
4. What is the symbol of a mirror for ray diagrams?
   • The symbol for a mirror in ray diagrams is a straight light with perpendicular lines on the back side.
5. What is it called when a wave hits a flat, shiny surface and bounces back?
   • When a wave hits an object like a mirror, and bounces back it is called specular reflection.
6. How does specular reflection allow an image to be formed?
   • In specular reflection rays are reflected at a consistent angle, allowing an image to be formed.
7. When does diffuse scattering occur?
   • Diffuse scattering occurs when rays are reflected from a surface in a variety of angles.
8. Why does a red object look red in white light?
   • A red object only reflects red light back to the observer. It absorbs all other colours.