1. -Standing Waves -Law of Reflection -Diffraction -Interference of Waves Physics Mrs. Coyle

2. Standing Wave http://www.physics.ohio-state.edu/~ntg/reu/gifs/cont_upright_wave.gif

3. Standing Waves Nodes: zero displacement Antinodes: maximum displacement http://sites.google.com/site/bromfieldphysics/Waves1.JPG

4. Forming a Standing Wave on a Rope Incident pulse interferes with the reflected (inverted) pulse. http://www.dacc.edu/~qchen/P102/labs/LAB5.HTM

5. How is a standing wave formed? Incident pulse Reflected pulse Standing wave http://www.physics.utoronto.ca/~jharlow/teaching/phy138_0708/lec05/index_files/image001.gif

6. Wave on a String (Applet) http://phet.colorado.edu/sims/wave-on-a- string/wave-on-a-string_en.html http://phet.colorado.edu/sims/wave-on-a- string/wave-on-a-string_en.html

7. Standing Waves Applet http://www3.interscience.wiley.com:8100/legacy/college/halliday/047 1320005/simulations6e/index.htm?newwindow=truehttp://www3.interscience.wiley.com:8100/legacy/college/halliday/047 1320005/simulations6e/index.htm?newwindow=true

8. L= 1/2 λ L= λ L= 1 1/2 λ L= 2 λ L=2 1/2 λ L=3 λ https://www.sciencebuddies.org/mentoring/project_ideas/Phys_img020.gif

9. Natural Frequencies of a Stretched String (Fixed Ends) Fundamental Frequency First Harmonic

10. Problem A string of length 1m vibrates. The speed of the wave in the material is 400m/s. Calculate the first three natural frequencies and draw the corresponding standing waves. Answer: 200Hz, 400Hz, 600Hz

11. Law of Reflection The angle of incidence equals the angle of reflection.

12. Refraction When a wave crosses a boundary between two different media, the wave changes direction because it changes velocity. Frequency is constant (as emitted from source) Velocity change is a result of wavelength change

13. Refraction

15. Why do ocean waves approach the beach parallel to the shore? Where is the speed greater? Hint: check the wavelength

16. Diffraction The bending of waves around a small obstacle or hole. The smaller the wavelength the smaller the diffraction.

17. One Wave Two Waves Interfering