1C10.62 - Time of Flight

Code Number:
Demo Title:
Time of Flight
Two - Dimensional Motion
Area of Study:
Masonite background, meter stick, short range spring gun, c-clamp, "sad" ball.

Set up two of the short range projectile guns side by side.  One should have an angle of 8-10 degrees, while the other should have an angle of 75 degrees.  Two cars are set in front of the guns, one being farther away from the guns than the other.  After the arrangement is described to the students the question is asked, "If both guns are fired simultaneously, with the same energy, which car gets hit first?"

  • Patrik Vogt, Jochen Kuhn, and Denis Neuschwander, "Determining Ball Velocities with Smartphones", TPT, Vol. 52, #6, Sept. 2014, p. 376.
  • "Editor's Note", TPT, Vol. 42, #5, May 2004, p. 261.
  • Paul G. Hewitt, "Physics Not Misfigured", TPT, Vol. 42, #5, May 2004, p. 260. 
  • Robert Weinstock, "Misfigured Physics", TPT, Vol. 42, #3, Mar. 2004, p. 132.
  • Paul Hewitt, "Figuring Physics: Projectile Speeds", TPT, Vol. 42, #1, Jan. 2004, p. 12, 45.
  • Fred Lang, "Solvable Equations", TPT, Vol. 38, #7, Oct. 2000, p. 389.
  • Michael George, "Answer C", TPT, Vol. 37, #8, Nov. 1999, p. 455.
  • John F. Goehl Jr., "Answer B", TPT, Vol. 37, #8, Nov. 1999, p. 455.
  • David Montalvo, "Author's Response", TPT, Vol. 37, #8, Nov. 1999, p. 454.
  • Brian Cahill and Thulsi Wickramasinghe, "Answer A", TPT, Vol. 37, #8, Nov. 1999, p. 454.
  • Clifford E. Swartz, "Questioning the 'Unsolvable'”, TPT, Vol. 37, #8, Nov. 1999, p. 454.
  • David Montalvo, "Solving an 'Unsolvable' Projectile-Motion Problem", TPT, Vol. 37, #4, Apr. 1999, p. 226.
  • Brian Cahill, Thulsi Wickramasinghe, David Montalvo, John F. Goehl, Jr., and Michael George, "Questioning  the
  • Earl Zwicker, "DOING Physics: Timing Projectile Motion", TPT, Vol. 26, #2, Feb. 1988, p. 124.
  • Robert D. Smith, "A Time-of-Flight Determination of the Monkey Hunter's Bullet", TPT, Vol. 13, #5, May 1975, p. 298.
  • Petre N. Henriksen, "Snowball Fighting: A Study in Projectile Motion", TPT, Vol. 13, #1, Jan. 1975, p. 43.
  • H. R. Kemp, "Trajectories of Projectiles in Air for Small Times of Flight", AJP, Vol. 55, #12, Dec. 1987, p. 1099.
  • A. Tan, C. H. Frick, and O. Castillo, "The Fly Ball Trajectory: An Older Approach Revisited", AJP, Vol. 55, #1, Jan. 1987, p. 37.
  • F. C. Peterson, "Timing the Flight of the Projectile in the Classical Ballistic Pendulum", AJP, Vol. 51 #7, July 1983, p. 602.
  • Glen E. Everett and R. L. Wild, "Inexpensive Time-of-Flight Velocity Measurements", AJP, Vol. 47, #5, May 1979, p. 426. 
  • M-162: "Baseball Timer", DICK and RAE Physics Demo Notebook.

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.