1. Waves: Take 2 Mr. Davis

2. p. 344 3,5,20,32,33,38,40,43,45

3. Review: Key characteristics of waves Period (if axis is time) Amplitude: The height of the wave from node to antinode (transverse waves), or the pressure in a compressive wave. Measured in units describing the wave Frequency: The rate of occurrence of the wave (in Hertz or cycles / second) Wavelength: The distance traversed by a full cycle of the wave Node: The “zero point” of the wave Antinode: The extreme point of the wave (max or min amplitude) Period: The time between successive waves The frequency f = 1/T where T is the period. All of these terms are required for the Regents

4. How does a string make music? What does a string look like when vibrating? How do I measure Amplitude Wavelength Frequency Period For each of these?

6. Videos: Superposition and wavelength as a function of gas composition http://www.acs.psu.edu/drussell/Demos/superposition/superposition.html http://www.wired.com/wiredscience/2008/0 9/top-10-amazing/

7. Standing waves Two similar periodic waves traveling in opposite directions form a standing wave.

9. L = /2 V = nf/2L

10. What happens when two waves collide?

11. What happens under the Cone of Silence? What happens when two waves collide? What happens when many people in the same room talk? What happens when an orchestra plays? What happens when waves interact in the ocean? (The Perfect Storm) What happens when two billiard balls collide?

12. They can cancel: Superposition (This is really addition of components of inverse sign) What happens when two waves collide?

13. They can add: Superposition What happens when two waves collide?

14. They pass through each other without affecting each other and keep on going

15. What happens when two waves collide? They pass through each other without changing and keep on going. (Have you ever crossed the beams of two flashlights to see what would happen?)

16. What happens when two waves collide? They pass through each other without changing and keep on going. (Have you ever crossed the beams of two flashlights to see what would happen?)

17. http://bestphysicsvideos.blogspot.com/2011/07/mit- physics-demo-wave-superposition.html MIT Demonstration of Bell Labs Wave machine

22. (7) (7)

23. Fundamental Frequency and Harmonics Two waves of similar frequency Beat frequency is the difference between them Beat Frequency

24. Speed of Waves Medium Wavelength (frequency) (temperature) (pressure) Waves have a speed! Dependent on Medium Temperature Pressure Frequency (wavelength) What about light?

25. Speed of Waves where v is the speed, f is the frequency, and lambda is the wavelength. v = f  What is v for a Slinky? What is v for sound? What is v for light? The relationship between wave speed, wavelength, and frequency is simple For a given temperature, pressure, material, etc.

26. Speed of Waves MediumSpeed (m/sec)FrequencyWavelength Sound340261 Light300,000,000700E-9 Ocean Wave251 Tsunami260 Earthquake P2 Earthquake Surface 0.5 Guitar String4251m http://www.pbs.org/wgbh/nova/earth/japan-killer-quake.html

27. Affects on sound waves Vibration (tension) Length Resonance Affects of sound waves Shatter glass! Transmit energy!

28. http://www.youtube.com/watch?v=w- qKlCy0T-g Sugar Plum Fairy: http://search.yahoo.com/r/_ylt=A0oG7qUs1zlPmVoAa6YPxQt.;_ylu=X3oD MTByMTNuNTZzBHNlYwNzcgRwb3MDMgRjb2xvA2FjMgR2dGlkAw-- /SIG=12095j2g1/EXP=1329219500/**http%3a//www.youtube.com/watch% 3fv=QdoTdG_VNV4 http://search.yahoo.com/r/_ylt=A0oG7qUs1zlPmVoAa6YPxQt.;_ylu=X3oD MTByMTNuNTZzBHNlYwNzcgRwb3MDMgRjb2xvA2FjMgR2dGlkAw-- /SIG=12095j2g1/EXP=1329219500/**http%3a//www.youtube.com/watch% 3fv=QdoTdG_VNV4 http://video.search.yahoo.com/video/play?p=sugar%20plum%20fairy%20 glasses&tnr=21&vid=1426162124191&l=207&turl=http%3A%2F%2Fts4.m m.bing.net%2Fvideos%2Fthumbnail.aspx%3Fq%3D1426162124191%26i d%3D4ac0756f0bc1187ac6dea26ab13b8515%26bid%3DQGXvePJox3gi Hw%26bn%3DThumb%26url%3Dhttp%253a%252f%252fwww.youtube.co m%252fwatch%253fv%253deQemvyyJ-- g&rurl=http%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DeQemvy yJ-- g&sigr=11a3bvfac&newfp=1&tit=%26quot%3BDance+of+the+Sugar+Plu m+Fairy%26quot%3B+on+the+Glass+Armonica%26quot%3B+on+the+Glass+Armonica http://www.youtube.com/watch?v=HpovwbPGEoo

29. Wave Videos Reflection off a sea wall: http://www.youtube.com/watch?v=PevRZAxDxZw http://www.youtube.com/watch?v=PevRZAxDxZw Big wave at beach: http://www.weather.com/blog/weather/8_21326.html http://www.weather.com/blog/weather/8_21326.html https://www.youtube.com/watch?v=QdoTdG_VNV4&feature =player_embedded#at=131 Tacoma narrows bridge: http://video.search.yahoo.com/search/video;_ylt=A2KLqIGXa SdPEn0AIxT7w8QF?p=tacoma+narrows+bridge&b=21&tnr=20