1. Bell Ringer 4-30-10 T/F: An electromagnetic wave requires a medium.
Electromagnetic waves can only be _____ (transverse, longitudinal).
List in order the parts of the electromagnetic spectrum.

2. Bell Ringer 4-30-10 A mechanical wave requires a ________.
What is the height of a wave called?
What is the length of a wave called?
What is the formula for frequency?
What unit measures frequency?

3. Chapter 15 Section 3 : Wave Interactions

4. Reflection
Refraction
Diffraction
Interference

5. 1. Reflection:
When a wave hits a reflecting surface, it is reflected outwards at the same angle as it came in.

6. 1. Reflection
Mirror
Incident light beam
Reflected light beam

7. 1. Reflection

8. 2. Refraction:
Waves bend when they go from one medium to another (like from air into water or glass)

9. 2. Refraction

10. 2. Refraction:

11. 2. Refraction
Different wavelengths bend at different angles, which is what makes a prism able to separate white light into all its colors
Refracted Colors
Air
White Light
Glass Prism

12. 2. Refraction

13. 2. Refraction
Refraction is also what makes lenses work. Light bends when it goes from air to glass.
Air
Incoming light
Focused light
Lens

14. 3. Diffraction
Light bends when it goes around around obstacles and through openings

15. Diffraction Examples Diffraction Examples
Diffraction of water waves (opening)
Diffraction of water waves (corner)

16. When two waves run into one another, they add if crests overlap, and subtract if troughs overlap
4. Interference

17. Interference and Diffraction