1M40.42 - Ballistic Pendulum - Sliding Block

Code Number:
Demo Title:
Ballistic Pendulum - Sliding Block
Conservation of Energy
Area of Study:
Vacuum Accelerator, Vacuum Pump, Ping Pong Balls, 650 gram Sliding Catch Block, Wooden Slide Board with attached Large Centimeter Scale.

Place all the apparatus onto the lecture bench and also make sure you secure the wooden slide board so that it can not move.  Then, line up the catch block so that the flat back surface is at the zero mark of the centimeter scale on the wooden slide board.  Place the vacuum accelerator so that there is very little space between the front of the catch block and the accelerator.  Make sure the vacuum accelerator is completely evacuated before you puncture the back membrane.  The block should slide approximately 20 to 25 centimeters when it catches the ping pong ball.  The ping pong ball has a mass of approximately 2.6 grams.

  • Cathy Abbot, "'Pretty Cool' Collision Experiment", TPT, Vol. 35, #7, Oct. 1997, p. 397.
  • Borislaw Bilash II, “Golf Ball Potential“, A Demo A Day – A Year of Physical Science Demonstrations, p. 250.
  • David P. Taylor, "The Ballistic Slider", TPT, Vol. 33, #7, Oct. 1995, p. 443.

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