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)
Linear Motor
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,
mathematics)
"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)
Predicting Paths:
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,
physics) Science
Songs
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,
retired) More
Science Songs
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