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Homework Help: Physics resistance force question (Newton's Laws)

  1. Oct 2, 2011 #1
    1. The problem statement, all variables and given/known data
    If a 25kg mass has a constant velocity of 5m/s, when pushed horizontally by a 5 N force, what amount of resistance force is present?

    2. Relevant equations
    F=ma

    3. The attempt at a solution

    I'm pretty sure the velocity is irrelevant, ... I made a diagram but that didn't help much. I'm not sure exactly what it is asking, aka I don't know what resistance force is or how to find it. I'm not sure where to start so any help would be appreciated!!!
     
  2. jcsd
  3. Oct 2, 2011 #2
    What are the horizontal forces on the mass?
     
  4. Oct 2, 2011 #3
    Just the 5 N right?
     
  5. Oct 2, 2011 #4
    Is the mass accelerating?
     
  6. Oct 2, 2011 #5
    No, it doesn't have any acceleration.
     
  7. Oct 2, 2011 #6
    Therefore it cannot have only the 5n force acting on it because otherwise it will acc.
     
  8. Oct 2, 2011 #7
    Ooohhh, I think I see what you're getting at. The resistance force must be 5 N also, right?
     
    Last edited: Oct 2, 2011
  9. Oct 3, 2011 #8
    Correct! Now you ARE thinking.
    Physics becomes easy... when you think enough.
    Now draw a diagram showing the forces and continue.
     
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