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Energy conservation check

  1. Mar 11, 2009 #1
    5) If there are no external forces acting on a system in the x direction, but there is an external force acting on the system in the y direction, then the y component of momentum of the system is constant.


    6) If work is done on an object by only conservative forces, then the momentum of that object must be conserved.


    7) The Work-Kinetic Energy theorem is invalid if work is done by a non-conservative force.


    I answered False, True, True.
    any sugestions?
  2. jcsd
  3. Mar 11, 2009 #2


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    Staff Emeritus
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    How about showing one's reasoning.
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