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Homework Help: Air Resistance

  1. Oct 25, 2007 #1
    1. The problem statement, all variables and given/known data

    What is the threshold or percent accuracy (100% like plus-minus 10%) of a freefall with air resistance?

    2. Relevant equations

    % accuracy = (actual_free_fall_time)/(ideal_free_fall_time)

    Computed Free Fall Time based on 9.8m/s^2 net force towards the ground. Actual refers to the actual in normal environment with the influence of air resistance.

    3. The attempt at a solution

  2. jcsd
  3. Oct 25, 2007 #2
    Have you got data to work with?? :S

    Or have you got to calculate it from air-density and a unit area?? I can't see how you would do that question, is that the whole question you posted??
  4. Oct 25, 2007 #3
    We got a ball falling at 50, 100 and 150cm. The ball's diameter is 2cm and it's weight is 50g and 100g. How about that?
  5. Oct 25, 2007 #4
    Oh right, is this a homework question?? Or something that you were just curious about??

  6. Oct 25, 2007 #5
    A homework problem. THanks.
  7. Oct 26, 2007 #6
    Well without going into very tricky calculus maths, you can't answer this simply. However, you can do this experimentally easily by timing the fall of objects as best you can. Maybe this is what the question is asking for :P
  8. Oct 26, 2007 #7


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    Homework Helper
    Gold Member

    I have to agree with everyone else. It seems that this problem either wants you to compare actual data for free fall with computed free-fall times, or it wants you to compare calculated values for both cases. The problem is is that it is not necessarily an intro physics problem when you add air resistance. Are you sure you don't have experimental free fall times given to you? This sounds like a lab problem.
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