7D20.10 - Mousetrap Chain Reaction

See procedure.
Code Number:
Demo Title:
Mousetrap Chain Reaction
Nuclear Fission
Area of Study:
Modern Physics
Mousetraps, about 75, Rubber Stoppers, Large Lucite Box, Camera and Power Supply.

Place the plate with the mousetraps mounted on it on top of the Lucite box base plate.   Set the traps and place two super ball neutrons on each trap.  Make sure one of the neutrons is sitting in the hole on the mousetrap.  When done setting all the neutrons you may place the cover on the apparatus.  Trigger by dropping a neutron in the hole in the cover.

Place the bottom of the Lucite box on a table, set the mousetraps and set them in rows on this bottom. Very carefully place the rubber stoppers on the mousetraps so that they have enough stability to be gently moved into the lecture room. Using one stopper as a trigger, drop it in the hole on the top of the Lucite box and observe the reaction. Preparation time is at least 30 minutes. This Demo has been video taped several times so that after you have done the reaction you can play the video in slow motion and see how the reaction evolves. The tape is in the video cabinet labeled 'Atomic Bomb - Mousetrap Exp.'.  

  • "Figuring Physics", TPT, Vol. 35, #9, Dec. 1997, p. 539. 
  • "Figuring Physics", TPT, Vol. 35, #8, Nov. 1997, p. 502.
  • Andrew DePino, Jr., "A Pile of Legos", TPT, Vol. 32, #5, May 1994, p. 300.
  • Robert Marzewski,  "Chain Reaction Model",  TPT, Vol. 26, #8, Nov. 1988, p. 514.
  • J. Higbie, "The Better Mousetrap: A Nuclear Chain Reaction Demonstartion", AJP, Vol. 48, #1, Jan. 1980, p. 86.
  • Hans G. Graetzer, "Discovery of Nuclear Fission", AJP, Vol. 32, #1, Jan. 1964, p. 9.
  • Esther B. Sparberg, "A Study of the Discovery of Fission", AJP, Vol. 32, #1, Jan. 1964, p. 2.
  • H. D. Rathgeber, "Mousetrap Model of Chain Reactions", AJP, Vol. 31, #1, Jan. 1963, p. 62.
  • MPa-1:  Freier and Anderson, A Demonstration Handbook for Physics.
  • S-260:  "Marbles in Saucer",  DICK and RAE Physics Demo Notebook.
  • S-265:  "Mouse Traps & Silicone Balls",  DICK and RAE Physics Demo Notebook.
  • Cy Tymoney, "Sneaky Atomic Fundamentals Simulation", Sneakiest Uses for Everyday Things, p. 124.
  • Bobby Mercer, "Chain Reaction", Junk Drawer Chemistry, 2016, p. 169.
  • Robert Ehrlich, "12.1 - Chain Reaction Simulation", Why Toast Lands Jelly-Side Down, p. 179.

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