12/12/08
Post date: Dec 11, 2008 5:56:22 PM
Bell Activity: What did you observe when waves went over the squares of glass?
Refraction
Waves pass into an area where the wave speed is different
Waves hit this area with a certain frequency (so many waves each second), and frequency does not change.
In order to compensate for a change in velocity, wavelength must change as well
Ocean waves
In deep ocean, have long wavelengths and fast speeds, very small amplitudes
Near shore (shallower water), waves slow down and pile up to make taller waves with shorter wavelengths.
Diffraction
Waves will bend around the edges of particles
Waves will spread into circular waves when they pass through a small opening
When several openings are near to each other, waves pass through and diffract (spread out) then interfere with each other on the other side.
Matter
If I throw tennis balls toward a gap between two walls, the balls either bounce off and come back toward me or go straight through the gap
If matter behaved like waves do, when the ball went through the gap it would explode and shoot out in all directions equally!
Other notes:
Wave types
Mechanical waves - require a medium
EM waves - do not need a medium
Sonar
If matter behaved like waves...
Work in groups of 3-4
Create an example of what our world would be like if matter behaved like waves
Example: ball thrown through gap between walls explodes and shoots out in all directions
Illustrate your example and share with the class
Chapter 14 Review
Reviewing Concepts: 3, 5, 10, 14, 17, 21
Applying Concepts: 1, 3, 6
Problems: 1, 4, 6, 8, 13, 15
Quiz on Monday - 25 points, covering chapter 14
For 5 bonus points on the quiz, draw a picture of what the world would be like if matter behaved like waves
We've discussed several "wave behaviors" so far, your picture should show what matter would look like if it were behaving in one of those ways.
Drawing must be in color
Include a short description of what's happening in the picture to show a wave behavior