User:Steven J. Koch/Physics 102 Stuff/02 Jan 27

Instructions

Please submit a few sentences explaining your answer to

exercise 12 from Chapter 11 ("Why is Brownian motion apparent only for microscopic particles?"). Think about the demo we did in class with the overhead projector and the small ball bearings and large ball bearings (which didn't work too well) as well as the wet paint / laser speckle demo. The objective is to gain more understanding by thinking and trying to write a good explanation.

Here are two web applets we may look at in class and which may help you on this assignment:

• <A href="http://galileoandeinstein.physics.virginia.edu/more_stuff/Applets/brownian/brownian.html" target=_blank>Simple applet</A>.  This one doesn't let you control anything, but is simple to use.
• <A href="http://www.physics.uq.edu.au/people/mcintyre/applets/brownian/brownian.html" target=_blank>Complicated and fun applet</A>  This applet is complicated because it has a lot of variables.  But it's also fun, and it simulates what should have happened in class on Thursday with the molecular motion demo.

I will publish the best answer(s) on WebCT for everyone to view, and possibly display in class.

See "HW Exercise Assignments" under "Course Content" for a list of all suggested problems.

Answers to this and other suggested exercises will be available after the due date.