1. Vibrations The Movement of Energy Music

2. Waves A transfer of energy over a distance in the form of a disturbance Wave originate from objects that are vibrating

3. This is cool so why not… https://www.youtube.com/watch?v=Ude8pPjawKI

4. Three Types of Vibrations 1. Transverse Vibrations  Occurs when an object vibrates perpendicular to its axis  ie. Guitar strings

5. Transverse Waves http://surendranath.tripod.com/Applets/Waves/Twave01/Twave01Applet.html

6. 2. Longitudinal Vibrations  Occurs when an object vibrates parallel to its axis  Ie. Shocks on a car or mountain bike

7. Longitudinal Waves http://surendranath.tripod.com/Applets/Waves/Lwave01/Lwave01Applet.html

8. 2. Torsional Vibrations  Occurs when an object twists around it’s axis  Ie. Washing machine

9.  Let’s hit the hallway…

10. Describing Vibrations Cycle  Occurs with a repeating event  One cycle – when an object returns to the place it started and it is moving in the same direction

11. Describing Vibrations Rest Position  Midway point between extremes in a cycle

12. Describing Vibrations Amplitude (A)  Displacement of object to either side of it's rest position

14. Describing Vibrations Frequency (f)  The number of cycles per second  Measured in Hertz (Hz)

15. Describing Vibrations 1 Hz = 1 cycle per second

16. Describing Vibrations Period (T)  The time required for one cycle  Measured in seconds

17. Formulas f = 1T = 1 T f f = # of cyclesT = Time Time # of cycles

18. Sample Problem If an electron vibrates back and forth with a frequency of 60 Hz, how long does it take to undergo one cycle?

19. Comparing Vibrations In Phase Vibrations  Pass the rest point at the same time  Same period of vibration

20. Comparing Vibrations Out of Phase Vibrations  Different period or same period but do not pass through the rest point at the same time