Wednesday, February 11, 2009

02/04/09 How Waves Travel

"...in groups write two things that you know about waves"

1) Oscillation
2) They can be added together without an increase in energy.


On the chalk board Professor Gleeson wrote some other properties of waves on the board.

- Crests and Troughs
- Waves refraction
- lambda = V/F
- Space and Time
- Energy!
- Transverse + Longitudinal
- Polarized (check out the blog picture)

We did discuss all of the proprieties above in class. However, I am only going to concentrate on the ones that interest me (OK...the ones that I understand the best!)

Of course the concept that I best understand is the relationship between the wavelength and frequency of a wave. This is a simple but fundamental equation to understand. It is simply:

^ = V/F , were ^=wavelength v=speed of the wave, and f= frequency

In the picture below three concepts above can be seen visually:



I also want to talk about polarized light. In a wave of light there are random oscillations of the electric field. When light waves oscillate in a particular way they are said to be polarized. Furthermore, when the light waves oscillates on a particular plane (x,y,z) it is said to be plane-polarized light. One use of plane polarized light is to determine the stereo-chemistry of an organic compound.



Furthermore, we also learned about refractive index. Each compound or substance has a refractive index. This number tells us how light waves, or sound waves travels though the compound. When waves travel though a compound they slow down. An animation of this concept can be seen below:



Sources:
(1) http://www.bom.gov.au/weather/radar/about/phase_changes.shtml
(2) http://au.encarta.msn.com/media_461531346/polarized_light.html
(3) http://www.uwgb.edu/dutchs/PETROLGY/GENLIGHT.HTM
(4) http://en.wikipedia.org/wiki/File:Snells_law_wavefronts.gif

No comments:

Post a Comment