1. Mechanical Waves and Sound
Ch. 17 Intro to Physics

2. Mechanical Waves Energy source cause vibration
Medium – material wave travels through

3. Types of Mechanical Waves
Transverse
Vibration perpendicular to direction

4. Type of Mechanical Waves
Longitudinal
Vibration parallel to direction
Surface
Only at surface

5. Properties of Mechanical Waves
Periodic – regular repetition by time
Period
Frequency
Hertz (Hz)
Wavelength

6. Properties Continued Wave Speed Amplitude
Speed = wavelength x frequency
Speed = wavelength/period
P. 506
Amplitude
Energy relationship

7. Behavior of Waves Reflection Refraction Bounce off
Speed and frequency same
Can flip
Refraction
Bend in new medium
Angled entry

8. Behavior Continued Diffraction Interference Bending due to obstacle
Around or through opening
Interference
Waves overlap and combine
Constructive
increase
Destructive
Decrease
P. 511

10. Standing Waves Appears to stay in one place Video Nodes Antinode
Stationary
Antinode
Between nodes
Crest or trough
Video

11. Sound Longitudinal Waves Intensity Loudness Frequency
How quickly wave’s energy flows
Decibel (dB)
Loudness
Frequency
Speed of vibration
Pitch
Length, tightness

12. Sound
Ultrasounds and Sonar
Doppler Effect
Sirens
Racetrack

13. Resonance Constructive interference Same frequencies together
Soundboards