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Pressure Help

  1. Jan 10, 2006 #1
    I'm working on the following problem:

    <i> A person who weighs 700 N is riding a 98 N mountain bike. Suppose the entire weight of the rider and bike is supported equally by the two tires. If the gauge pressure in each tire is 7.55 105 Pa, what is the area of contact between each tire and the ground?<i>

    The equation that I'm trying to incorporate is P = F/A where P equals pressure, F equals perpendicular force and A equals area. So I figured that since the tires are supporting the entire weight of the bike and man, the combined force that would be used in this problem would be 798N. So I rearranged the formula to equal A = F/P. So I said 798N / 7.55E5 N/m^2 would equal 1.06E-3m^2. Of course webassign says that my answer is incorrect. Any constructive help would be appreciated.
  2. jcsd
  3. Jan 10, 2006 #2


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    Homework Helper

    "each tire and the ground" , not "both tires".
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