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Few collisions as possible

  1. Nov 12, 2009 #1
    1. The problem statement, all variables and given/known data
    A frictionless puck of mass m slides down a ramp with considerable speed. You wish to slow it down by having it collide (not necessarily head-on) with other pucks at rest with as few collisions as possible. What mass would you choose for the pucks at rest? (The same physics in this problem is essentially the same as that in slowing down neutrons in a nuclear reactor)

    2. Relevant equations

    There is a figure, but it just displays a frictionless puck sliding down a slide onto a table covered in a bunch of other pucks. There are no values.

    3. The attempt at a solution
  2. jcsd
  3. Nov 13, 2009 #2
    Hi there,

    Take the energy and momentum conservation principles to figure out this one.

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