Fall 2015

Mechanics, heat/thermodynamics

August 15, 2015 at USC

Sponsored by SCAAPT and the Brown Foundation

James

Bill

Frank

  • PowerPoint presentation
  • First Day of School, Intro to physics - Dan Burns' Physics of Roadrunner
    Related: Science on the Simpsons (also curated by Dan Burns)
  • Newton's Laws
  • Circular motion
    • Circular motion - Analysis of object released from circular motion
      • Click here for sample student data video
      • Open the video file in Quicktime. Pause the video. Press the left and right arrow keys to advance back and forward one frame at a time.
      • If you have Windows and don't want to (or can't) install Quicktime, you can do frame-by-frame using Windows Media Player. You must right-click => Enhancements => Play Speed Settings. The little arrows will advance or reverse one frame, but sometime's it's a little buggy for me.
      • Video Physics app for Apple devices (mentioned by participant Catherine)
  • Thermal expansion demos
    • Propane tank and nozzle are available at hardware stores as a bundle for $15-20. Tanks of propane (the blue container, don't get red or yellow) cost ~$3 and last at least an entire day's worth of demos.
    • Ball-and-Ring demo (donated by Ward's Science)
      I follow up with the questions "Why does the ball get bigger?" "What's the difference between a hot and cold substance?" I have students come up with possible models (molecules get bigger, molecules get further apart, molecules speed up, etc.). Which one of these models best fits (explains) how the ball got bigger? What about why when a hot object touches a cold object, the cold get hotter and the hot gets colder? I also do the hot/cold water food color demo to nudge students in the direction that molecules have more kinetic energy ("move faster") as temperature increases.
    • Application of thermal expansion: shrink fitting
      The cooled inner part warms and expands, causing an extremely snug fit without requiring hardware or adhesives
    • Bi-metallic strip demo
      Google Image search for "bimetallic strip"
      Applications - thermostats, blinking "holiday lights"
  • Graph sorting activity
    • Link to MS Word document of graphs and descriptions (download and open in MS Word - don't directly open using Google Drive)
      A participant suggested a way to scaffold this activity: Give students just the written descriptions and have them read those. Then, give them the position vs. time graphs and have them match those to the written descriptions. Last, give them the velocity vs. time graphs to match to the existing pairs.
    • A participant (sorry, forgot who) shared another way to structure the activity is to have every student hold one card, then they must find their match.
  • Reaction time meter stick lab
    • Participant Vicky shared that she also has her students distract the catcher by having the partner do something like sing to them, and another version in which the catcher is texting. How do these affect the reaction time?
  • Constant velocity buggies
    • Metronome Online
    • Make a "slow" buggy by replacing a battery with a bullet-shaped wad of aluminum foil the size of a battery
    • Extension: If a fast and slow buggy were placed x cm apart, where (and when) would they collide? A precise answer can be found using algebra (system of equations), or an approximate answer can be found using a position vs. time graph.
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Frank Lee,
Aug 16, 2015, 9:53 PM
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Frank Lee,
Aug 15, 2015, 5:46 PM