Random Walk

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 Code Number :    8B10.35

Disclaimer:

Reprinted by permission of Dick Berg, University of Maryland, for use on this website.

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Condition :   Good  
Principle :   Particle Movement in a Stellar Core 
Area of Study :  Astronomy   
Equipment :   Random Walk Apparatus, balls of different sizes, molecular motion demonstrator, plexiglass plate with pins, steel ball bearing.

Procedure :   Place one of the neon golf balls in the center of the random walk and turn it on.  The speed of the random walk can be varied using the dimmer switch, however the unit usually does not start moving until the dimmer switch is turned almost all the way up.  The pegs in the board have different spacing so that depending upon the size of the ball no exclusion, some exclusion, or all exclusion will be observed.  A good run on this apparatus will last about 30 seconds.

The molecular motion demonstrator with the plexiglass plate and pins will also do a fair job of showing random walk.  This also has the advantage that the particle will not fall out of the apparatus. 

Several "Bumble Balls" in an enclosed area or large table top will also give a demonstration of a random walk. 

 

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   References

Michael Zeilik, "Modeling Energy Outflow in Stars", TPT, Vol. 37, # 4, Apr. 1999, p. 236.

 

R. Dean Astumian, "Paradoxical Games and a Minimal Model for a Brownian Motor", AJP, Vol. 73, # 2, Feb. 2005, p. 178.

Cyril Domb, "Random Walks and Diffusion", AJP, Vol. 46, (1), Jan. 1978, p. 49.

 

5.26, "Demonstration 4", Project & Demonstrations in Astronomy by D.Tattersfield, p. 111.



Mail Questions and Comments to:  Dale Stille