This java applet shows the physics behind a beam of light impinging at some angle


The java applet was divided into two region lower half (water) and upper half (air).

Click links to switch: between water-air and  air-water cases



Usage: You will find a flashlight under the water surface. (Picture)


Another similar applet can be found at [url=http://www.phy.ntnu.edu.tw/ntnujava/viewtopic.php?t=527]Intensity of reflected s-wave/p-wave
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Check out the following URL if you are interested in [url=http://www.szwholesale.com/choose_a_personal_flashlight.php]Guide To Choosing A Personal Flashlight[/url].


http://www.youtube.com/watch?v=mcOCrPCbyq4

http://www.youtube.com/watch?v=9SMEf8nHTjI