High School Biology-Chemistry SMILE Meeting
02 December 2003
Notes Prepared by Porter Johnson

Ann Parham and Winifred Malvin [Carver Elementary School]         Bernoulli's Law
Ann and Winifred
started by mixing about 25 mL of liquid detergent with about l Liter of water, inside a clear plastic container. They then used the sudsy water to make bubbles, which we used to illustrate and study Bernoulli's Law.  Some details are given by the article Bubbularium (make an observatory to see the amazing colors in bubbles) http://www.exploratorium.edu/science_explorer/bub_dome.html, at the S. F. Exploratorium website.  In addition, activities are described on the Bubble-ology & Bernoulli website [http://www.scoe.org/content.php?PageId=208]

Winifred briefly talked about Bernoulli's Principle and its relation to flight, and we did some activities in bubble-ology.  We divided into groups of 3-4, which began to conjure up and investigate strategies for keeping a bubble in the air.  Each group had about 100 mL of sudsy water as well as a straw, and we went to work!  Carol Giles found that it was very effective to fan the air above the bubble with a sheet of paper.  Why does that work? Should we ask Bernoulli?

Winifred and Ann then followed the instructions in the Bubbelarium article, making and studying fantastic bubbles.  We saw great images and rainbows in the bubbles.  How come?

Just sensational! Thanks.

Joyce Bordelon [Moos Elementary School]     Flight and Glider Construction
gave us information and templates obtained from the article entitled 757 Glider Kit (in pdf format) http://www.nasa.gov/audience/foreducators/topnav/materials/listbytype/757.Glider.Kit.html, which is located on the NASA Spacelink Educational Materials website:  http://www.nasa.gov/audience/foreducators/topnav/materials/about/index.html.  We then proceeded with a very successful launch of gliders, using the information obtained there.

The gliders were a big hit! Great, Joyce.

Barbara Pawela [May School, retired]        Surface Tension of Water:  Handout
led us through a miniteach that she developed in the Summer 1995 SMILE Programch9510.html..  The activities involved a study of adhesion, cohesion, molecular attraction, and surface tension --- as well as their role in detergents and other cleaning agents.  

We love these classic lessons; they are timeless and relevant ---  and lots of fun!  (just  like the reruns of I Love Lucy©) Thanks Barbara!

Marva Anyanwu [Wendell Green Elementary School]        Surface Tension of Water, continued!
introduced still more exercises on surface tension, which we will finish next week. We began by dividing into groups, with each group being given about 65 mL of milk in a Styrofoam plate.  We investigated phenomena associated with mixing, using food coloring (three different colors) as well as liquid detergent. Each group developed its own approach to investigating the matter --- hypotheses, expected results, procedures, conclusions. Swirls of color were formed when the colored drops were dropped into the milk.  New colors were formed when two regions of two different color were stirred together.  When a droplet of detergent was added to a region of a given color, the color change propagated from the location of the droplet outward.  As described in the previous miniteach, this propagation by diffusion occurs because of the surface tension of the water--- the primary ingredient of milk.  It was especially impressive to watch the propagation, because it was so easy to see the colors change.

Thanks, Marva!