1N21.20 - Air Track - Mass & Momentum Transfer

Code Number:
Demo Title:
Air Track - Mass & Momentum Transfer
Momentum, Action - Reaction
Area of Study:
Air Track, Car with Catcher, Car with Projectile Launcher, and a Set of Balls Containing 3 Each of Al, Fe, and Pb.

Set the cars so they are 10-15 cm apart on a level air track. Place the desired number of balls into the projectile launcher. The launcher will hold up to three balls at a time. The balls we have are Al at 10.23 g each, Fe at 28.84 g each, and Pb at 36.67 g each. After you start the timer on the projectile launcher you should still have 5-8 seconds to steady the two cars before the projectile is launched. Both the recoil on the launching car and the momentum transfer to the catching car maybe observed.

  • Paul Hewitt, "Answer to April Figuring Physics", TPT, Vol. 53, #5, May 2015, p. 315.
  • F. Herrmann and M. Schubart, "Measuring Momentum Without the use of p=mv in a Demonstration Experiment", AJP, Vol. 57, #9, Sep. 1989, p. 858. 
  • Julius Sumner Miller, Q39 & A39, Millergrams I – Some Enchanting Questions for Enquiring Minds, p. 33 & 89.

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