1. Wave Behaviors We will discuss different manners in which a wave can behave when it comes in contact with matter or other waves!

2. 1. Reflection
REFLECTION – occurs when a wave strikes an object or surface and bounces off
Examples – mirrors, seeing colors
All types of waves – SOUND, WATER, and LIGHT can be reflected
ECHO – when a sound wave hits another object which reflects it back to you

3. 1. Reflection INCIDENT BEAM – the beam striking a reflective object
REFLECTED BEAM – the beam that bounces off a reflective object
NORMAL – line drawn perpendicular to the surface of the reflective object
ANGLE OF INCIDENCE (i) –angle formed by the incidence beam and normal

4. 1. Reflection
ANGLE OF REFLECTION (r) – angle formed by the reflected beam and normal
LAW OF REFLECTION – the angle of incidence is equal to the angle of reflection

5. 1. Reflection

6. 1. Reflection

7. 2. Refraction
REFRACTION – the bending of a wave (changes direction) caused by a change in its speed as it moves from one medium to another. The GREATER the change in speed, the MORE the wave bends.
Examples: eye glasses, contact lenses, microscopes, sparkle of a diamond, prism hanging in a window

8. 2. Refraction
                                                                            

9. 3. Diffraction
DIFFRACTION – object causes a wave to change direction and bend around it
Examples: ______ waves change direction when they bend around islands (water waves bending), _________ someone from around a corner (sound waves bending)

10. Refraction vs. Diffraction
A. Both cause waves to BEND
B. Refraction occurs when waves pass THROUGH an object
C. Diffraction occurs when waves pass AROUND an object

11. 3. Diffraction

12. 4. Interference
INTERFERENCE – the ability of two or more waves to combine and form a new wave when they overlap
This new wave exists only while the two original waves continue to OVERLAP

13. 4. Interference
A) CONSTRUCTIVE INTERFERENCE – waves added together as they overlap
A. CRESTS of two waves arrive at the same place at the same time
B. Amplitude of new wave is equal to the SUM of the amplitudes of the original wave

14. 4. Interference

15. 4. Interference

16. 4. Interference
B) Destructive interference – waves subtract from each other as they overlap
A. Crest of one wave meets TROUGH of the other wave
The amplitude of new wave equal to the DIFFERENCE between the amplitudes of the waves that overlapped

17. 4. Interference

18. 5. Standing Wave
STANDING WAVE – special type of wave pattern that forms when waves are equal in wavelength and amplitude but travel in opposite directions continuously interfering with each other
Ex: string of a violin is played with a bow, it vibrates and creates standing waves in the string to create a rich tone

19. 5. Standing Wave