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Homework Help: Order-Of-Magnitude = Pain

  1. Jul 31, 2004 #1
    Hi, my physics lecture gave us such a stupid and annoying question as follows:

    1.Without looking up any data, estimate the amouint of rubber that is lost per kn from the four tires of a typical car.

    2.For a busy street, how many cars pass per year

    Any idea?
  2. jcsd
  3. Aug 1, 2004 #2
    1.) i think you meant km, I suppose that a tire lasts 15,000 km and maybe wears 4 or 5 mm. These are bs but you get the picture.
    2.) Assume 50 km/h, and maybe 6 metres between each car.. Say its only "busy" half the time because of lights and time of day etc. Basically, calculate how many pass by a certain point. If you don't like these numbers choose your own but you get the idea.
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