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Homework Help: Question about acceleration/forces

  1. Jun 22, 2005 #1
    My homework question asks...
    "If you stand next to a wall on a frictionless skateboard and push the wall with a force of 30 N, how hward does the wall push on you? If your mass is 60 kg, what is your acceleration?"
    I figured that the wall pushes on you with a force of 30 N back, but what is the net force to be used in the equation to find acceleration? Is it 0, or 30?
     
  2. jcsd
  3. Jun 22, 2005 #2
    Try to imagine the problem. What would happen if YOU were in the same position. Would you stand still? No. So use 30=60.a
     
  4. Jun 22, 2005 #3
    only 1 horizontal force is acting on you -- that of the wall pushing back on you with 30 N force.

    the "other" horizontal force (you pushing the wall) is not acting on you, but rather is acting on the wall

    to calculate horizontal acceleration, use F = ma
     
    Last edited: Jun 22, 2005
  5. Jun 22, 2005 #4
    You wouldn't stand still, so it would be 30 divided by 60?
     
    Last edited: Jun 22, 2005
  6. Jun 22, 2005 #5
    thanks that really clears things up!
     
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