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I can't quite understand the concept of force.Force = Mass *

  1. Jan 19, 2012 #1
    I can't quite understand the concept of force.

    Force = Mass * Acceleration

    Work = Force * Distance

    If you apply a force to an object, and it doesn't move, no work has been done. Yet if an object doesn't move, how can there be acceleration? So based on that, no force has been exerted?

    And also, if you try to move an object for example a stapler across your desk, you need to apply a constant force to it to keep it moving at a constant velocity, so that force is equal to the force exerted by the friction. So if you apply a force equal to the opposing force, the net forces cancel out and you get no acceleration. So does that mean that to get the stapler to move in the first place, more force than what the friction value is, was necessary to get the stapler to begin moving (in order to change the inertia/invoke a new vector of force on the mass of the stapler?).
    Last edited: Jan 19, 2012
  2. jcsd
  3. Jan 19, 2012 #2

    Doc Al

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    Staff: Mentor

    Re: Force

    Better to think of this as ƩF = ma: net force on an object equals mass * acceleration.

    It just means that the net force on the object is zero, not that you exerted no force.

    Right! In order to start something moving you must accelerate it, which requires a net force.
  4. Jan 19, 2012 #3
    Re: Force

    That makes more sense now, thanks!
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