Science Buddies: "Ask an Expert"

I'm going to do this project, but do not know many of the things they are talking about. For example, how would I use Snell's law and refraction to calculate the speed of light? Can someone give me a step by step on what to do, how to measure the angles, etc.?
Thanks

Hi,

I assume you are trying to do this project:

https://www.sciencebuddies.org/science- ... p009.shtml

I agree that the writeup of this project assumes that you should figure a lot out by yourself. The place to start is by reading all the links in the Bibliography section, which collectively will tell you what snell's law is and how it relates to the speend of light in various media. The problem is that you have to read ALL of the linked references. I strongly recommend doing this before anything else. There is also a simulator on one of these links that lets you do quick “experiments” to see how light refracts between different sets of media - play with this, including changing the angle of light incidence until snells law makes sense to you.

Many people will devise an experimental setup that uses a protracter to measure the angles of incidence and refraction. Just be sure that the place where the laser beam strikes the jello surface is at the center of the protracter or you angle measurements will be off.

If, after reading the project bibliography references, you are still confused these sites might help:

http://www.school-for-champions.com/sci ... _snell.htm

http://en.wikipedia.org/wiki/Snell's_law

http://www.usc.edu/CSSF/Current/Projects/J1916.pdf

http://wiki.answers.com/Q/How_do_you_us ... t_in_jello

http://wildcat.phys.northwestern.edu/Lab/snell.pdf

My last tip is that if you have trouble seeing the laser beam in air you can make it visible by introducing dust into the air (you can use flour to make dust if all else fails).

Good luck and have fun with the project!

Barrett L Tomlinson