1. Chapter 5, Section 2 Making Waves

2. January 5, 2011 HW: PTG #1, 2, 5-8, pg. 505-506, Due Monday, Bring Tissues Learning Objective: – Describe how waves carry energy – Describe how wavelength, frequency and speed of a wave are related Success Criteria: – Observe the motion of a pulse – Calculate the speed of a wave pulse – Observe standing waves – Investigate the relationship among wave speed, wavelength, and frequency – Make a model of wave motion – Distinguish between transverse and longitudinal waves Do Now: – 5.1 Quiz – Write LO and SC on a new left- side page – WDYS/WDYT pg. 492

3. Investigate: Part A Stadium Wave Standing Wave #1-Answer a-d in your notebook

4. January 6, 2011 HW: PTG #1, 2, 5-8, pg. 505-506, Due Monday, Bring Tissues Learning Objective: – Describe how waves carry energy – Describe how wavelength, frequency and speed of a wave are related Success Criteria: – Observe the motion of a pulse – Calculate the speed of a wave pulse – Observe standing waves – Investigate the relationship among wave speed, wavelength, and frequency – Make a model of wave motion – Distinguish between transverse and longitudinal waves Do Now: – Brain Dump: List everything you know about waves

5. Part A Big Idea? Wave moves, but people stay stationary Waves are produced by adjacent particles move up and down, causing the wave to move across.

6. Investigate: Part B Transverse Waves Demo #1-5 You are writing in your notebook #6-7-in groups #7-choose amplitude as a class – Prediction: How do you think amplitude will affect the speed of the wave? – Groups 1-2, 3-4, 5-6 different amplitudes

7. #10-13 Demo then in groups #14-Demo, discuss energy #15-groups, discuss

8. Part B Big Ideas Speed of a wave=distance/time Frequency=#times the wave moves up and down each second Energy travels in waves Transverse Wave: Standing Wave:

9. Investigate: Part C Longitudinal Waves Complete all sections, OK with teacher

10. Part C Big Ideas Compressional/Longitudinal Waves

11. Investigate: Part D Skip

12. Vocabulary Activity Book Definition:Definition in YOUR words ExamplePicture or Equation

13. Physics Talk Waves Transfer Energy Example A wave transfers energy with no transfer of mass When you throw a ball the mass and kinetic energy move from one place to another A wave transfers only energy, no mass is moving.

14. Physics Talk How is energy transferred? Chemical energy in muscles  mechanical energy in arm  spring Energy transferred from one form to another, but TOTAL energy remains the same…Conservation of Energy!

15. Physics Talk How do waves “add”? They continue to travel as though the other wave never existed. http://www.youtube. com/watch?v=Xqo6sE t1cUE http://www.youtube. com/watch?v=Xqo6sE t1cUE

16. Physics Talk Periodic Wave Crest Trough Amplitude Repetitive series of pulses Highest point on a periodic wave Lowest point on a periodic wave Height of crest or depth of trough

17. Physics Talk How does amplitude relate to sound? How does amplitude relate to energy? Large amplitude  Loud sound! Small amplitude  soft sound Large amplitude  Large amount of energy Small amplitude  small amount of energy

18. Wavelength (λ) Frequency (f) Distance between two consecutive crests or troughs Symbol is λ (pronounce lambda) Number of waves per unit time Usually waves/sec called hertz (Hz)

19. Physics Talk Period (T) Time required to complete one complete wave (crest-trough-crest) Period and frequency are inversely proportionate P=1/f f=1/T

20. Physics Talk Transverse Waves Compressional (Longitudinal) Wave The medium moves perpendicular to the direction of the wave The medium moves parallel to the direction of the wave http://www.youtube.c om/watch?v=MoVz2ENJ b8M

21. Physics Talk Standing Wave Wave pattern that remains in a constant position. Does not go right/left, but does go up/down. http://www.youtube. com/watch?v=03cUrk jqdE0 http://www.youtube. com/watch?v=03cUrk jqdE0

22. Node Antinode Place on a standing wave that is motionless Point on a standing wave where the displacement (movement) is greatest

23. What type of wave is sound? Compression Wave Air molecules get compressed and move through the air

24. How can you calculate the speed of a wave? Speed=Distance/Time Wave speed=wave frequency x wavelength v=fλ Sample problems on pg. 502

25. Essential Questions Pg. 504 – What does it mean? – How do you know? – Why should you care?

26. HW: PTG #1, 2, 5-8, pg. 505-506