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Homework Help: Help With Free Fall

  1. Jan 4, 2010 #1
    The problem statement, all variables and given/known data[/b]
    Problem: How much Air Resistance acts on a 100-N bag of nails that falls at its teminal speed?

    What process do you use to solve this?
  2. jcsd
  3. Jan 4, 2010 #2


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    At terminal velocity the resultant force on it is zero, so find the expression for the resultant force and equate to zero.
  4. Jan 4, 2010 #3
    What have you tried so far? Do you understand the properties behind terminal speed?
  5. Jan 4, 2010 #4
    I'm asking if I need to use F=ma to solve this. And if I do, where are each of the numbers plugged in?
  6. Jan 4, 2010 #5
    This should be more than enough for you to solve the problem.

    Make some attempts and if you're still stuck we'll go from there.
  7. Jan 4, 2010 #6
    Still don't know what to do? How do you find the expression for the resultant force?
  8. Jan 4, 2010 #7
    To obtain an expression for the resultant force you have to understand what the resultant force is! ;)

    The resultant force is what you get when you sum up all the forces acting on a given object.

    What forces are acting on the object?
  9. Jan 4, 2010 #8
    Air resistance, and gravity are the forces acting on the object, right?
  10. Jan 4, 2010 #9
    Fg (Force of Gravity) - Ff (Force of Friction) = Fr (Resultant Force)
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