1N30.15 - Newton's Trough

Code Number:
Demo Title:
Newton's Trough
Area of Study:
"U" track, 1 inch ball bearings.

Place 4 or 5 balls on the track.  Roll another ball into these and observe that a ball at the other end of the row is ejected.  Roll two ball into these and observe that two balls at the other end of the row are ejected, etc.  You can make this a discrepant event by using one or two 1 inch round magnets in place of a couple of the normal 1 inch ball bearings.  This is another form of "Newton's Spheres".  See 1N30.10 for that demonstration.

  • Robert Ehrlich, "E.6, Colliding Balls on a Grooved Ruler", Turn the World Inside Out, p. 57.
  • Borislaw Bilash II, David Maiullo, "Newton's Trough", A Demo a Day: A Year of Physics Demonstrations, p. 105.

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