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Cycle question

  1. Oct 9, 2005 #1
    The cyclist got a average speed of 1,8m/s and a top speed of 3,6sek
    The time is 10 sek.
    How do I get to know how long will the cyclist cycle the last 5 sek of the 10 sek. Can i conclude that with my formula?

    Please help me
  2. jcsd
  3. Oct 9, 2005 #2


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    Homework Helper

    If you mean that the top speed is 2 times the average speed, then
    (in first approximation of constant acceleration) the lowest speed was zero.
    So the graph of velocity vs time is through the origin, straight-line.

    How far did he go in the whole 10 seconds? (½ vmax tmax)
    this is the area of the triangle "under the curve" v vs t .

    How far would he go, in the last half of the race?
    (OK, what would his average speed be during this half?)
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