1. Resonance
19hz sound

2. Resonance
Objects will vibrate at their resonance frequency when acted upon
Resonance frequency depends on size, material, tension, etc.

3. Resonance What will wave of swing look like?
What if you push harder or softer?
What changes?
How could you change its resonance frequency?

4. Resonance
What would break this glass? Blasting it with a bass guitar or a soprano?
What does this say about the resonance frequency of a glass?

5. Do car bodies have high or low resonance frequencies? How do you know?

6. Resonance

7. Resonance
Using resonance frequencies to levitate object

8. Resonance Frequency of swing is 1.5 swings per second (sps)‏
What if you pushed at 1.5, 2, 3, 4.5, 5 sps?
What does this have to do with harmonics?

9. Resonance
Would the glass vibrate if you blasted it with a bass guitar? How long would it continue to vibrate?
How about with a soprano's voice?

10. Mythbusters and the breaking glass
Resonance
Mythbusters and the breaking glass

11. Little kid breaking glass
Resonance
Little kid breaking glass

12. Resonance
Damping: when something causes the amplitude of a vibration to weaken.
e.g. Felt pad on piano string, touching drum head.
Objects (due to size, material, etc.) have frequencies they damp.

13. Damping effect of gel on motor mount
Resonance
Damping effect of gel on motor mount

14. Why not put short violin strings on this?
Resonance
Why not put short violin strings on this?

15. Why not put a small chamber under the drum head?
Resonance
Why not put a small chamber under the drum head?

16. What happens to the resonance curve as the banjo head is loosened?

17. Resonance Highly damped resonators:
1) resonate with a wider range of frequencies.
2) resonate less strongly.
3) start to vibrate quickly and stop vibrating quickly.
4) have flatter resonance curves.

18. Resonance

19. Resonance Lightly damped: guitar string, tuning fork
Heavily damped: guitar sound board, car body, vocal tract

20. Resonance

21. Resonance

22. Resonance
Bandwidth: The frequencies a resonator is effective at vibrating at. (The middle part of the curve.)‏
What is the relationship between damping and bandwidth?

23. Resonance
Flute

24. Resonators are filters. They damp some frequencies and amplify others.
Resonance
Resonators are filters.
They damp some frequencies and amplify others.

25. What does all of this have to do with speech?
Resonance
What does all of this have to do with speech?

26. Resonance The vocal folds produce a complex wave.
The F0 of the complex wave can vary (pitch).
The vocal tract is a filter that emphasizes some frequencies and damps other.
When the vocal tract changes shape it changes its resonance frequencies.

27. Mythbusters
Infrasound