10 September 2002: Fred Schaal (Lane Tech HS,
on Famous Trains
Fred made a summer junket to the West by traveling on several famous trains, taking the following route:
Fred pointed out that one may still travel on these legendary trains, although the concept of a time schedule is vague to non-existent these days. Fred commented that the tongues on the back portion of "double semi" trucks on Western roads were very long, and asked why they were constructed in this way. Fred also asked what happens when the "unitized rails" become loose, since the forces tending toward expansion are very large on warm days. Any ideas on either of these questions? Thanks, Fred.Empire Builder: Chicago ® ® ® Seattle
Cascades: Seattle ® ® ® Vancouver BC
Coast Satellite: Vancouver ® ® ® Emeryville CA
Southwest Chief: Emeryville ® ® ® Los Angeles
Sunrise Limited: Los Angeles ® ® ® Dallas
Texas Eagle: Dallas ® ® ® Chicago
08 October 2002: Fred Farnell [Lane Tech HS,
Physics] A Slow Train
Fred used traction feed computer paper to lay out a 27 meter "track" on the floor of his classroom. He released a slow-moving, battery-operated toy train engine [He got it at Radio Shack; it requires 4 batteries for operation.], which students kept on the paper track by pushing it occasionally with a stick. Students were located along the track with stop-watches to record the time required for the train to travel to their locations. A distance-time graph was constructed from the data, which was a fairly straight line of slope 0.5 meters/sec. [A smaller, faster toy made the 27 meter trek in about 13 seconds.] The speed-time and acceleration-time graphs were constructed from the distance-time graph by taking slopes. He signaled the students to begin timing by lowering a rod that he held over his head --- this method of initiation is similar to the music conductor's downbeat, which signals the orchestra to begin playing a piece. A fresh approach, Fred. We knew that bigger is better, and sometimes slower is better, as well.
22 October 2002: Fred Schaal [Lane Tech HS,
Riding the Rails --- Again!
Fred continued to describe his rail travels around the country, indicating that in a number of passenger stations there engines of ancient vintage on display. He saw the legendary Union Pacific Big Boy 4884 steam locomotive in one station; for details on that engine see the Union Pacific Big Boys website http://www.steamlocomotive.com/bigboy/. There were also a number of diesel locomotives of ancient vintage on display.
Fred asked why there were different couplers on tank cars, which were much higher off the ground. It was suggested that such an arrangement would decrease the likelihood of punctures of tank cars during train wrecks, since hazardous materials are routinely transported in tank cars. Porter Johnson mentioned that the coupling mechanism on American trains [from Tierra del Fuego to Valdez; automatic coupling] is different from that on European trains [mechanical coupling with hydraulic plungers to maintain stability], whereas Lego®.Trains use magnets for coupling [http://en.wikipedia.org/wiki/Lego_Trains]. For additional information see the website Military Traffic Management: http://www.tea.army.mil/DEP/TRANSPORT/modes/rail/nylon.htm. You seem to enjoy hearing the squeal of the train wheels, Fred!
10 December 2002: Don Kanner [Lane Tech HS,
Concerning the Motion of a Toy Train
Don set up a toy train, consisting of an engine operated with dry cell batteries along with a coal car and two other cars, which moved on a circular track about 60 cm in diameter. He handed out a Surprise Quiz, consisting of these 3 questions:
Don attached a paper circle of larger diameter to the end of a large can [say, a coffee can], and rolled it along the front edge of the table with the paper circle sticking over the front of the table. One could see quite clearly that the point at the bottom of the circle was moving backwards as the can rolled forward without slipping on the table. Don, we we don't love a surprise quiz, but we do love The Little Engine That Could ... Make Us Think! Keep the ideas rolling!
Porter put a red diode laser pointer [with the switch held in the "on" position with an alligator clip] on the coal car of the train. As the train moved around in a circle, the laser produced a "headlight" beam that went in the direction of motion of the train. When the lights in the room were turned off, the sweeping headlight swept dramatically and somewhat eerily around the room. Porter pointed out that this system is a good model for the Advanced Photon Source [APS] [http://www.aps.anl.gov] at Argonne National Laboratory, in which the beam of electrons goes around and around the ring for hours and hours, and that the synchrotron radiation comes out strongly peaked about the instantaneous direction of the ultra-relativistic electron beam. To be more realistic, one should get a blue laser diode, since the visible component of Synchrotron Radiation increases with decreasing wavelength.
09 September 2003: Fred Schaal [Lane Tech HS,
Tank Cars and Mars
Fred noticed while traveling on Amtrak through Kansas last summer that there were pipes connecting a large number of tanker cars together. Does anybody know what was being transported, and why the tanks were connected? Fred also expressed disappointment at being unable to see the planet Mars during its closest approach to earth in several thousand years. Has anybody else seen its polar ice caps? You may have left Kansas and gone into the Land of Oz, Fred! Interesting questions!
21 October 2003: Fred Schaal [Lane
Tech HS, mathematics]
the Great Divide
Fred traveled extensively on the Union Pacific Main Line last summer, during which he noticed that a number of the tank cars were "sway backed". He wondered why they were built that way. During the discussion, the following points were raised:
14 September 2004: Fred Schaal [Lane Tech HS,
Green Line Adventure
Fred described a recent incident on a CTA EL train late in the evening, in which thugs were beating up a man who would not give them his money. Fred pressed the emergency button --- then the driver took the train quickly to the next station --- then the doors opened --- and then the thugs ran away into the night. He wondered whether the thugs could have been captured if the driver had delayed the train between stations, giving the police time to get to the next stop. There was no clear consensus as to what would have been the best course to follow. Porter Johnson commented that, although CTA security may seem lax at times, they do occasionally crack down upon passengers who behave improperly. Earl Zwicker passed around copies of two columns by John Kass, which appeared recently in the Chicago Tribune. These columns concerned an IIT student who was ticketed by a policeman for $50 for sleeping on the EL. It is impossible to catch all the miscreants, it seems!
Very exciting, Fred!
13 September 2005: 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.viarail.ca/en/useful-info/.
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!
18 October 2005: Don Kanner (Lane Tech,
Physics with MSTS: Microsoft Train Simulator
Don projected an image of the instrument panel of a locomotive on the screen at the front of the class. He used the MSTS locomotive simulator, which can be run on a computer to teach physics in class. Two (brake) pressure gauges, a speedometer, a digital clock, a Train Status indicator, and a Force Gauge were visible. Don highly recommends the Print Screen™ software program on Windows™ to save images at time intervals from this (or any other) program to a folder of your choice. See also this URL: http://www.download.com/Print-Screen-Deluxe/3000-2094_4-10356546.html?tag=lst-0-2. In addition, see the (free, downloadable) Picasa2 Picture Editing Software: http://picasa.google.com/index.html. These screens then can be used as a data set to help with problems involving, for example, speed and distance versus time, for uniform linear acceleration, variable acceleration, and circular motion. In particular a decrease in acceleration for a certain locomotive automatically occurs at a speed of 45 m/s, with a corresponding decrease in force, explained by Newton's Second Law. This locomotive is programmed to accelerate more quickly at low speed, and less quickly at high speed, to stay on schedule. Good stuff! Thanks, Don.
18 October 2005: Fred Schaal (Lane Tech HS,
RR on the GD (RailRoading on the Great
Fred handed out a sheet he had gotten concerning the American Orient Express [http://american-orient-express-train.com/trips.shtml], which is now bankrupt.