1D60.10 - Property of Inertia Demo - Jeep & Gun

Code Number:
Demo Title:
Property of Inertia Demo - Jeep & Gun
Area of Study:
Jeep with Spring-Loaded Gun and Metal Rod for Gun.

This demonstration works best if care is taken to pull the pin straight out of the hole. Deceleration of the jeep occurs if the pin is pulled at any appreciable angle. Make sure that the jeep does not fall off the lecture bench as this could bend the attached spring gun.

The track for the Pasco apparatus must be level before starting. Also make sure the gun alignment is correct. This may be adjusted with the screws adjustments on the gun mechanism. Mount the triggering flag at the proper height. When the cart and gun are pushed down the track the gun will automatically fire when triggered by the flag.

Another version of this demonstration with the Pasco apparatus is to use a bridge to cover a portion of the track. If the gun it triggered before it hits the bridge the ball should shoot over the bridge and be caught in the car at it emerges from under the bridge.

  • Richard P. Hechter, "Hockey, IPads, and Projectile Motion in a Physics Classroom", TPT, Vol. 51, #6, Sept. 2013, p. 346.
  • T. Kranjc and N. Razpet, "A School Experiment in Kinematics: Shooting From a Ballistic Cart", TPT, Vol. 49, #7, Oct. 2011, p. 442.
  • Nicholas Schardl, "Problem-Solving Challenges", TPT, Vol. 37, #3, Mar. 1999, p. 161.
  • Raymond A. Serway, Jim Lehman, and Richard Hall, "The Ballistic Cart on an Incline Revisited", TPT, Vol. 33, #9, Dec. 1995, p. 578.
  • Scott Welty, "Frames of Reference", TPT, Vol. 26, #4, Apr. 1988, p. 245.
  • Albert A. Bartlett, "Modified Ballistic Car Demonstration", AJP, Vol. 43, #8, Aug. 1975, p. 732.
  • George Barnes, "Projectile Gun for an Air-Track Glider", TPT, Vol. 12, #3, Mar. 1974, p. 177. 
  • Fred B. Otto, "Modified Ballistic Car Demonstration", AJP, Vol. 42, #4, Apr. 1974, p. 326.
  • W. Louis Bartlett, Winston Renoud, "Relative Motion Car for the Air Track", AJP, Vol. 41, #4, April 1973, p. 580.
  • Mb- 24: Freier and Anderson,  A Demonstration Handbook For Physics.
  • M-182:  "Projectile Cart",  DICK and RAE Physics Demo Notebook.
  • M- 99, Richard Manliffe Sutton,  Demonstration Experiments in Physics.
  • Julien Clinton Sprott, "1.3, Ballistics Car", Physics Demonstrations, ISBN 0-299-21580-6, p. 8.
  • Borislaw Bilash II and David Maiullo, "Projectile Cart", A Demo a Day: A Year of Physics Demonstrations, p. 49.
  • Borislaw Bilash II and David Maiullo, "Rollerball", A Demo a Day: A Year of Physics Demonstrations, p. 47.
  • Julius Sumner Miller, Q44 & A44, Millergrams I – Some Enchanting Questions for Enquiring Minds, p. 35 & 92.

Disclaimer: These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist.  The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose.  The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources.  Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks.  These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage.  Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.