Particle Diffusion In Stellar Medium - Percolation & Convection Cells



Image #2
Image #3


content.gif (1503 bytes)
 Code Number :   2B40.55?  

Disclaimer:

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

The demonstrations contained and referenced herein are listed for the purposes of cataloging and describing physics demonstrations which should be conducted only under the direction of a trained instructional support professional or physicist. These demonstrations are not presented for the purpose of being conducted by persons unconnected to this Facility and/or persons not consulting with or being supervised by the recognized instructional support professional or physicist and his/her staff. The University is responsible only for those demonstrations carried out using its own equipment using established safety and scheduling policies, and bears no responsibility for those choosing to use this source material for their own purposes. All demonstrations described and contained herein are public domain, and can also be found in reference materials in libraries, bookstores, and electronic sources.

Further information regarding legal liability in use of demonstrations and labs will be found on the web site Injuries in School/College Laboratories in USA.

The University of Iowa Disclaimers:  University of Iowa Disclaimer All Rights Reserved..

Condition :   Good  
Principle :   Percolation and Density Gradients  
Area of Study :  Astronomy   
Equipment :   Test Tubes and Corks, Baby Oil or Mineral Oil, Water, Soap (Joy), Camera And Power Supply, Lab Jack , Lucite with Holes, Test Tube Holder.

  
Procedure :   Fill three test tubes half full of colored water, and put baby or mineral oil in the other half. In one of the tubes put 1 or 2 drops of soap. Use one of the half and half mixtures as a reference. Take the other half and half mixture and the tube with the soap and shake vigorously. Put them back in the holder and watch the percolation type separation, and the time differences.

Turn on the lava lamp at least 2 hours before demonstration time.  When the lamp reaches normal temperatures convection cells may be observed.  These convection cells are basically isolated regions that have gained heat and therefore changed their density.  When heated it will rise until it cools off significantly.  When it cools the density increases and it starts to sink.

conbot.gif (53 bytes)


   References

Gustavo Ariel Schwartz, Silvio J. Luduena, "An Experimental Method for Studying Two-Dimensional Percolation", AJP, Vol. 72, # 3, Mar. 2004, p. 364.

 

Janice Vancleave, "Immiscible,"  Chemistry for Every Kid - 101 Experiments That Really Work, pp. 168-169.

Janice VanCleave,  "Riser,"  Guide to More of the Best Science Fair Projects, pp. 90.



Mail Questions and Comments to:  Dale Stille