1L20.66/7D30.90 - Orbits on the Overhead/Mass Spectrometer Model

Code Number:
Demo Title:
Orbits on the Overhead/Mass Spectrometer Model
Orbits Around a Gravity Well
Area of Study:
Mechanics and Astronomy
Overhead plate with ball bearings.

See also 1L20.66 in Mechanics and 7D30.90 in Modern Physics.

Place the Plexiglas plate with attached ring magnet on the overhead projector.  Roll one of the ball bearings at a grazing angle across the ring magnet.  Watch the ball bearing either be deflected to a different direction, or orbit the magnet.

  • Michel Gagnon, "A Mass Spectrometer Simulator in Your Computer", TPT, Vol. 50, # 9, Dec. 2012, p. 553.
  • Matthew Lowry, "Teaching Universal Gravitation with Vector Games", TPT, Vol. 46, # 9, December 2008, p. 519.
  • S - 190: "Atoms, Molecules and Solids", DICK and RAE Physics Demo Notebook.
  • David Kutliroff, "A Mass Spectrograph Analog", 101 Classroom Demonstrations and Experiments for Teaching Physics, p. 219.
  • Borislaw Bilash II, David Maiullo, "Model of Mass Spectrometer: A Demo A Day: A Year of Physics Demonstrations, p. 293.

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