1. Waves

2. Wave Motion A wave travels along its medium, but the individual particles just move up and down.

3. . Wave Motion A wave pulse begins with a vibrations which is transmitted by internal forces in the medium. Continuous waves start with vibrations too. If the vibration is SHM, then the wave will be sinusoidal

4. Waves Transmission Except for light all waves need a medium to transmit These are known as mechanical waves “In space no one can hear you scream”

5. Transverse Waves In transverse waves the motion of particles is perpendicular to the wave direction

6. Longitudinal Waves In longitudinal waves the motion of particles is parallel to the wave direction. “along” with the wave

7. Sound Waves Sound Waves are longitudinal waves

8. Crest – highest point above equilibrium Trough – lowest point below equilibrium Amplitude – distance from equilibrium to a crest or trough Wavelength – distance wave travels during one cycle, usually measured from crest to crest or trough to trough Wave Characteristics

9. Wave Simulation http://phet.colorado.edu/en/simulation/wave-on-a- string http://phet.colorado.edu/en/simulation/wave-on-a- string

10. Wave Characteristics Period – how long it takes a wave to complete one cycle Frequency – how many cycles a wave can complete in a given amount of time (1 second) Wave Speed – how fast a wave is travelling, depends on the medium

11. Wave Speed

12. Wave Problems A tuning fork produces a sound wave with a wavelength of 0.20 m and a velocity of 25.6 m/s. What is the frequency of the tuning fork? A wave moving along a rope has a wavelength (l) of 1.2 m and a frequency (f) of 4.5 hz. How fast is the wave traveling along the rope?