Date: Fri, 5 Mar 2004 13:14:54 -0500

Author: Wolfgang Rueckner

Subject: Re: Maxwell Velocity Distribution


The website doesn't give you a clear idea 'cause I never documented
it. Could take a picture of it sometime if there's interest. In any
case, the top is replaced by a tall transparent plastic box (same
footprint as bottom) which has plastic troughs (gutters) spanning the
inside at different levels. The troughs are slightly tilted with a
hole at the bottom end to let balls roll out. The system reaches an
equilibrium state as the troughs fill with balls and balls leave the
troughs (through the hole). Comparing the number of balls at any
time in different height troughs gives an indication of the density
of balls that were able to reach that height. (The balls with the
greater initial K.E. are the ones that reach the greater heights,
etc.) -- hope that makes some sense -- Wolf

>The spinning plate with ridges is a great approach. I've tried to make a
>vibrating floor work, and it just isn't an efficient way to get the
>particles kicked around.
> What is the setup of your Maxwell velocity distribution? What did you
>do to collect and analyze the velocities? (The website doesn't give me a
>clear idea.)
>Jason St. John 617.353.2634
>Boston University Physics Lecture Demonstrations
>590 Commonwealth Ave. Boston, MA 02215
>On 2004-03-05.11:54 sent:
>Jerry -- I built an 2nd story addition to our "golf-ball atmosphere"
>demo many years ago
>to show the velocity distribution as a function of height. It worked
>reasonably well and showed the effect within a minute or so of
>operation. Haven't used it since (it was a special request by one
>faculty member at the time). -- Wolfgang
>>I would like to revive an earlier thread about the Maxwell Velocity
>>Distribution. Some questions for Tappers:
>>Which Tappers have a demo for the Maxwell Velocity Distribution?
>>If you have a demo for this where did you get it?
>>Which Tappers do NOT demonstrate for the Maxwell Velocity Distribution?
>>Please respond and elaborate if you have time.
>>This topic had been discussed in earlier threads. Urs uses the
>>Phywe Maxwell Velocity Distribution device and I am considering to
>>purchase one. Jason Saint John is making a homemade device.
>>Michael Thomason had a software simulation but I am not interested
>>in a simulation.
>>I have had repeated requests from faculty to perform this experiment.
>>Thanks, Jerry
>>Gerald Zani e-mail:
>>Manager of Demonstrations phone: (401) 863-3964
>>Department of Physics FAX: (401) 863-2024
>>Brown University Providence, RI 02912-1843 USA
>>Do a little more of that work which you have confessed to be good,
>>Which you feel that society and your most Just Judge rightly demand of you.
>>Cultivate the tree which you have found to bear fruit in your soil.
>>If you have any experiments you would like to try, try them.
>>Now's your chance.
>>Henry David Thoreau, Journal entry, 1850.
From Fri Mar 5 13:43:22 2004