Roy Coleman (Morgan Park HS, physics)
SMILE CD Available
Roy offered his CD's with a wealth of SMILE lessons from all the years of the program and additional shareware [Open Office®, Mozilla®, etc] that Roy has put on the disc; the cost is $10. The disc also has a video of invited demonstrations done by Chicago's Academic Alliances at an AAPT meeting at Notre Dame University some years ago.
Earl Zwicker (IIT, retired)
Earl showed us a Linear Motor that illustrates some interesting aspects of electromagnetism. Marilynn Stone volunteered to check it out, and then to report back to us later, and perhaps to give us a demonstration!
Fred Schaal (Lane Tech HS,
"VIA Rail Canada" vs "Amtrak"
Fred told us about his trips this summer on VIA Rail Canada [http://www.viarail.ca/en_index.html] and Amtrak [http://www.amtrak.com/], particularly about riding in the observation ("dome") car. On the Canadian trains Fred did get a good view of the train, all the way up to the engine, and beyond that. However, the trains were so long that the animals had already run away in fright, so that he did not see many of them along the way. In addition, the glass tended to be poor quality. The Canadian rail system extends over more than 5000 km from Halifax (NS) to Vancouver (BC). Fred called attention to the North America Rail Pass, which permits rail travel throughout the United States and Canada: http://www.internationalrail.com/north-america.aspx.
While traveling near Winnipeg, Fred noticed the funny red rocks outside the train. He had noticed the Precambrian Shield or Laurentian Plateau, which covers a large portion of Northern Canada. For details see the Canadian Shield website: http://www.nationmaster.com/encyclopedia/Canadian-Shield. Thanks Fred!
Paul Fracaro (Joliet Central HS,
physics) CBL System
Paul demonstrated math and physics lessons on the CBL (Calculator Based Laboratory) System. A collection of lab exercises is available in these disciplines, as described in the following books:
Paul demonstrated the ultrasonic position detector/probe as an example. He projected the screen from the calculator onto a large movie screen in the front us, so we could follow along as he walked us through the software. The sensor was linked to an interface, which in turn was linked to a TI-83 calculator. For example, the calculator plotted a distance versus time relationship as Paul walked backward and then forward, as the sensor detected his position. Using the same setup, Paul walked forward and backward over a time interval of about 5 seconds. A plot of position versus time showed up on the calculator/screen, from which the velocity could be obtained by clicking on two points on the graph. Paul tried to walk so as to match the following graph of position versus time, using the detector to record his positions:
He found it surprisingly difficult to move with a constant velocity, although it was rather easy to be at rest. Detection probes are also available for sound, magnetism, electricity, temperature, force, etc. Paul described a nifty experiment on Newton's Law of Cooling using the temperature probe. Simply wrap the probe in aluminum foil, heat it with a blow dryer, and take data on temperature versus time, yielding an exponential curve. Neat stuff, Paul! Thanks.
Karlene Joseph (Lane Tech HS, physics)
Exercises for Critical Thinking
Karlene has been searching for problems for her students that get away from "plug and chug" and more towards critical thinking. One she called "Predicting Paths". The first example was a hoop that was marked with a point on its circumference. Karlene slowly rolled the hoop on the (flat, horizontal) table. She asked her students to visualize/determine the path traveled by the single point as the hoop rolls in one direction. Several of us commented that the curve is a cycloid -- the special case of a Brachistochrone is described below.
A similar question involves a hoop with the point rolling on the inside of a fixed circle. The curve here might be called an epicycloid. A third one is like the second but now the outer (large) hoop rolls while the inner hoop is stationary -- like a point on the edge of a Hula Hoop. The next time around Karlene asked her students to design an apparatus to give a physical demonstration of the process and the results. One student represented the cycloid visually by taping a flashlight onto the inside edge of a coffee can, and rolling the can across the table. Nifty! Thanks for the ideas, Karlene!
Porter had us consider an application, the Brachistochrone problem, posed by Johann Bernoulli in 1696 --- see Brachistochrone Problem: http://www-groups.dcs.st-and.ac.uk/~history/HistTopics/Brachistochrone.html. Here is a simple statement of the problem:
Let us connect two fixed points, A and B, by a wire that maintains its shape. What is the optimal shape of the wire, for a bead (of constant weight) to slide down the wire from A to B -- without friction -- in the shortest time?This question was the first one solved using The Calculus of Variations. For additional details see the website The Brachistochrone: http://whistleralley.com/brachistochrone/brachistochrone.htm.
Bill Colson (Morgan Park HS,
Bill gave us a great link to funny songs with themes from physics or chemistry, on the Haverford College website: http://www.haverford.edu/physics-astro/songs/.
Bill also found an article which describes Adidas1 self-adjusting running shoes, advertised as the World's First Intelligent Shoe [http://www.thefreelibrary.com/adidas+Introduces+the+World's+First+Intelligent+Basketball+Shoe.-a0138943598], available for about $250. See the September 2005 issue of Consumer Reports magazine; http://www.consumerreports.org/main/home.jsp.; Check the website http://www.computergear.com/ for computer gifts, T-shirts and gadgets for geeks, nerds, techies, and computer enthusiasts!
Bill also reported on Nextfest 2005 [http://www.technovelgy.com/ct/Science-Fiction-News.asp?NewsNum=409], sponsored by Wired Magazine -- a neat expo held at Navy Pier, June 24-26, 2005. It was a festival of new innovations of various types, including visits by the Cloned Cats! Bill commented that teachers are able to see IMAX films at Navy Pier at no charge a few weeks after their opening. For details see the Navy Pier IMAX Education Connection website: http://www.imax.com/oo/navy-pier-imax/groups-and-field-trips/imax-educators-connections/. Great, Bill!
Bill Blunk (Joliet,
Bill spent the summer near Glacier National Park and visited with Richard (Dick) Schwab, a professor at UC Davis, an expert on Gutenberg Bibles. Dick's roommate at Harvard University was Tom Lehrer! In 1951 the physics class put on a review session which in fact was a revue of great songs written by them. Go to The Physical Revue website: http://www.haverford.edu/physics-astro/songs/lehrer/physrev.htm. We couldn't (as Bill had planned) get to the web site and play some of that stuff for us. He was able to play us Snell's Law -- Macarena Style, as obtained from the website http://www.haverford.edu/physics-astro/songs/macsnell_music.htm. It concerns Willebrord Snell (1580-1626), who is credited with discovering Snell's Law of Refraction. For details concerning Snell see the St Andrews University website http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Snell.html, from which the following has been excerpted:
"... Although he discovered the law of refraction, a basis of modern geometric optics, in 1621, he did not publish it and only in 1703 did it become known when Huygens [http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Huygens.html] published Snell's result in Dioptrica. Snell also discovered the sine law. ..."This might be a great way to lighten up a physics class. Thanks, Bill!
Ann Brandon (Joliet west,
retired) NSTA Magazine
Ann shared with us the September 2005 issue of the NSTA Science Teacher magazine, which emphasized safety in the classroom. There was a great article on doing chemical flame tests safely and an article showing a sharp increase in accidents in science labs as the number of students in a classroom grew to exceed 24. Thanks, Ann!
Notes prepared by Ben Stark and Porter Johnson