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Inclined plane acceleration

  1. May 10, 2010 #1
    Consider the classical physics problem of a cube sitting atop a frictionless inclined plane. Of course, this cube will accelerate down the plane with acceleration dictated by F = mgsin(theta), where theta is the angle between the inclined plane and the horizontal surface.

    Easy enough.

    Now, my question is this; if the inclined plane was itself sitting atop a frictionless, horizontal plane, would it too accelerate in some direction as the cube slides down its surface? In order to conserve momentum, for instance?
     
  2. jcsd
  3. May 10, 2010 #2

    sophiecentaur

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    Just write out the force equation and that should do it. Have faith, my lad! Physics works.
     
  4. May 10, 2010 #3

    jack action

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    The cube would have a simple vertical free fall and the inclined plane would move out of its way as the cube goes down since it doesn't have any restriction.
     
  5. May 10, 2010 #4

    Doc Al

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    Of course.

    The cube is not in free fall. The incline exerts a force on it.
     
  6. May 10, 2010 #5

    sophiecentaur

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    The cube and the ramp will move apart horizontally - Newton's Third Law - in addition to the cube moving vertically.
     
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