Information:

• Write-ups for academic year SMILE meetings for the current semester may be found at http://www.iit.edu/~johnsonp/acysmile.html, and write-ups from previous semesters are permanently located at http://www.iit.edu/~smile/biweekly.htm.
• Your hang tag for parking at IIT is valid in the parking lot by the Keating Gymnasium on Tuesday afternoons, 4-6:30 pm, until the end of the Spring semester 2006.  Be sure to put this hang tag on your inside rear view mirror when you park here.
• Earl Zwicker called attention to a thriving sales of water taken from the depths of the Pacific Ocean near Hawaii.  This water, which  is remarkably free of industrial contaminants, is partially desalinated by a reverse osmosis process by Koya USA Corporation, and then bottled and sold to Japanese consumers.
• Global Positioning System Activity:
  • Date: Saturday, January 21, 2006 - 12 noon to 4 pm.
  • Location:  Midewin National Tallgrass Prairie, Wilmington IL.
  • Cost: $35.00
  • Goals: Technology training on GPS; Guaranteed to get you out of the office mentally; Experience using GPS units with an introduction to geocaching, one of the fastest growing activities.
  • Information, registration form and flyer are available at The GIS to GPS Portal:  http:// www.gis2gps.com.
  For details on future meetings of the Illinois State Physics Project [ISPP] see their website: http://ispp.info.  For details concerning Physics Northwest meetings see their website:  https://www.edline.net/pages/Physics_Northwest.

Fred Schaal (Lane Tech)               Conserving the Heat of my toes
Fred recently broke his leg and has had a cast. How should Fred keep his toes warm with just the little "boot" that is provided to put over his stockinged foot?. He put a stocking cap over his toes, with a plastic bag over the cap, the entire "apparatus" being held in place with a bungee cord. Very enterprising, Fred!

Nneka Anigbogu  (Jones College Prep)                  Random rectangles
Nneka handed out a sheet with 100 rectangles of various dimensions displayed.  Each rectangle was composed one or more identical squares.  Our activity was to obtain an estimate of the average number of squares.  This is an activity to illustrate use of statistics. Nneka asked us to briefly look at the 100 rectangles and to shout out estimates of the average area of all 100 in "standard units" (easy because each had an area that was an integral number of the standard squares mentioned above. Estimated averages were 8, 9, 11, 17, 50. Then Nneka had us choose any 5 rectangles in a "continuous run" (e.g., rectangles 5-9) and estimate the average of those 5. We got averages of 1-12.8, for 10 samples of 5 rectangles, with an overall average of 8.82. This completed the "subjective estimate" of the mean.

Nneke also handed out a table of 450 five digit random numbers. We used the table to pick 5 numbers and use any consecutive two digits from that five digit number, match these with the numbers of the corresponding rectangles, and get another group of 5-rectangle averages. Ten averages ranged from 4.0- 8.6, with an overall average of 5.81, the "random estimate" of the mean.

It turns out that the actual average of the 100 rectangles is 7.42. Surprisingly, the subjective estimate was a bit closer to the actual than the random estimate. Nneka noted that in her class the random method gave a number almost identical to the actual average. How come ours was so far off?  Great stuff! Thanks, Nneka.

Charlotte Wood-Harrington (Gwendolyn Brooks HS)                National Boards
Charlotte recently became a certified as a physics teacher by the National Board of Professional Teaching Standards:  http://www.nbpts.org. It was a long, hard process, but she felt it was worthwhile. The current out-of-pocket cost of the program is $300. Charlotte gets a stipend from the State of Illinois for $2500-3000 per year for ten years.  Charlotte used the Chicago Teachers Union as a sponsor to the process. It has a very high rate of passing, but it requires a 25 page application (there is also an entrance through the PHD (Professional Honor of Distinction) program. Charlotte said that the writing requirement for the board exam involved a new skill that had to be learned. There are 6 subject matter tests (30 minutes each) as well as submission of videos made in the classroom. It took 2 years to complete, and seemed to Charlotte to be a little harder than getting a masters degree. Regarding the material level in the process, it is probably most likely that one would have to be a high school teacher to be successful in the process.  Thanks for the encouragement and the information, Charlotte!

Arlyn Van Ek (Illiana Christian HS)                 Odds and ends
Arlyn attended a recent meeting of  the National Science Teachers Association  [NSTA] in Chicago, which was great!  He brought back these neat odds and ends to share:

• First were squares of black construction paper (about 5 cm on a side). Each had a different colored dot on each side and could be arranged to spin quickly when blown. Through persistence of vision, we saw a combination of the two colors as a third color upon spinning.
• Next was a simple spectroscope made from a cardboard tube with a piece of CD-R disc (cut as a circular shape to fit over one end as the diffraction grating) and a circular piece of construction paper with a slit in it at the other end. The spectrum is viewed from the end with the CD-R piece.  The (mailing) tubes were obtained from ULINE Shipping Supply Specialists:  http://www.uline.com/Class_15.asp?desc=Tubes.
• Next was an optical illusion. A white, translucent plastic Halloween mask that is three-dimensional to fit over the face and held to be concave. When illuminated below, it appears as if it were convex. He mentioned another optical illusion, the Ames Window Illusion:  http://www.discover.com/educators-guide-archive/jan-03/guide3/.
• Next was a pingpong ball with three LEDs of different colors inside and a circuit that causes the various LEDs to light in various combinations (in a preset sequence). The various combinations of LEDs lighting produced about six different colors, blinking off and on in sequence.
• Next was a small electric motor running a propeller taped to its battery off center and suspended from a string. The apparatus spun, which resulted in a standing wave being generated in the string with one node where Arlyn was holding it, one node where it connected to the apparatus, and several nodes along its length. When green light from a laser pen illuminated the string, the string had an orange glow.  Apparently, the string consisted of fluorescent material, with secondary emission of lower frequency orange light when illuminated by the green laser.
• Next was the world's smallest motor. A small  Neodymium magnet was stuck on the head of a nail --- now magnetized --  then suspended at its point from the metal base of an AA battery.  A wire from the + pole of the battery was held in light contact with the magnet/nail head, and the nail would spin, as a torque was produced by the passage of a current perpendicular to the magnetic field.

Bud Schultz (Aurora Middle School Academy)              Easy primitive toy
Bud showed us a "bull roarer" which is an Australian aboriginal toy. It operates to produce a roaring sound when it rotates in two planes. The bull roarer is a piece of wood carved to be about the size and shape of a spear head and suspended from a string of about 2 meters in length. Different shapes can be made; Bud's were carved out of Padauk  -- a reddish wood from Africa: http://www.exotic-wood.com/african_padauk.htm.  First Bud spun the bull roarer, --- then he held the string at the other end, and twirled the bull roarer in a vertical circle.  The sound was not produced until the rotation became quite rapid -- it requires both rapid rotation and simultaneous spinning in a second plane.  For additional information see the Virginia Tech Multimedia Music Dictionary:  http://www.music.vt.edu/musicdictionary/textb/Bull-roarer.html. Wow-wow-wow!  Thanks, Bud.

Larry Alofs showed us the inside of a combination lock apparatus, which might once have been a locking door for a post office box. There are three round tumbler plates inside the lock, each having a notch. Each number of the combination rotates one of the plates so that the notch is aligned in a certain direction. The right sequence of numbers serves to align the three notches on the three plates, which allows the lock to be opened. Neat!  Thanks, Larry.

Porter Johnson then told us the story of how Richard Feynman, who, during his time at Los Alamos working on development of the  atomic bomb during WWII, devised a way to open combination locks. He first made these observations:

• Most people leave an open combination lock at the position of the last number in the combination.
• Most combination locks will open if you get fairly close to the precise number in the combination.

The following people could not present lessons today, because we ran out of time. They will be scheduled for our last SMILE meeting of the semester, Tuesday December 13. See you there!

• Bill Colson: Catalogues / Stamps
• Carl Martikean: Biochemistry

Notes prepared by Ben Stark and Porter Johnson.