1N30.45 - Inelastic Collision - Speed of a Ball

See procedure.
Code Number:
Demo Title:
Inelastic Collision - Speed of a Ball
Conservation of Linear Momentum, Impulse
Area of Study:
Balls, Ball Catcher or Box With Crumpled Newspaper, Inclined plane.

Set the inclined plane so that it will shoot the ball into the ball catcher.  The speed of the ball as it leaves the inclined can be calculated by how far the catcher moves on the table after it catches the ball.  Balls of different mass may be used.  The angle of the incline can also be changed.

A less accurate method is to throw a ball into a box of crumpled newspaper.  Measuring how far the box travels will give you a rough estimate of the speed of the ball as it left your hand.  Compare this calculation to the speed measured with a radar gun if possible.

  • Edward J. Finn, "Linear Momentum Conservation in a Nonconservative Environment", AJP, Vol. 42, #1, Jan. 1974, p. 54.
  • Borislaw Bilash II, David Maiullo, "What's My Speed", A Demo a Day: A Year of Physics Demonstrations, p. 120.

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