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Homework Help: Very simple question.

  1. Nov 4, 2006 #1
    We have a block on a frictionless inclined plain. Someone's hand is pushing the block up with constant velocity. So, the forces acting on the block are the normal force, gravitational force...and is that it? I mean the block is moving at constant speed upward so why should that be a force. I think Im wrong here...but why?
  2. jcsd
  3. Nov 4, 2006 #2
    Yes that's it
  4. Nov 4, 2006 #3


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    The block is moving at constant speed. That means no acceleration. No acceleration ==> no force. But as you said, there is gravity and a normal force acting on the block. So it must be that the hand pushing the block exerts a force such that it counter-balances the other 2 and makes the net force 0.
  5. Nov 4, 2006 #4
    no *net* force, of course, like you say at the end :)
  6. Nov 4, 2006 #5
    Sorry, my mistake. Of course Quasar is right
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