1. APHY201 2/3/2016 1 11.6 Resonance   Matching an object’s natural frequency with an external force   Since most objects have elastic properties, resonance can cause them to be damaged or destroyed.   Breaking a glass with sound Breaking a glass with sound   Tacoma Narrows Bridge Tacoma Narrows Bridge   Bridge in Russia Bridge in Russia

2. APHY201 2/3/2016 2 11.7 Wave Motion   Oscillations that move through matter and carry energy.

3. APHY201 2/3/2016 3 11.7 Wave Motion   Wave speed   For a string:

4. APHY201 2/3/2016 4 11.8 Types of Waves   Transverse and Longitudinal   Example 1 Example 1

5. APHY201 2/3/2016 5 11.8 Types of Waves   Earthquakes and Water Earthquakes

6. APHY201 2/3/2016 6 11.9 Energy Transported by Waves

7. APHY201 2/3/2016 7 11.11 Reflection and Transmission of Waves   Newton’s 3 rd Law   Similar to a wave traveling Similar to a wave traveling from water into oil

8. APHY201 2/3/2016 8 11.12 Principle of Superposition   Constructive and destructive interference In phase or out of phase?

9. APHY201 2/3/2016 9 11.13 Standing Waves   Due to the superposition of the waves at certain frequencies Fundamental Frequency Overtones or Harmonics

10. APHY201 2/3/2016 10 In class: Problems 54, 82 Other problems ↓ 41. To find the time for a pulse to travel from one end of the cord to the other, the velocity of the pulse on the cord must be known. For a cord under tension, we have.