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Homework Help: Mechanics question.

  1. Oct 11, 2008 #1
    1. The problem statement, all variables and given/known data

    Two cyclists, A and B, have displacements 0 Km and 70 Km, respectively. At t = 0 they begin to cycle towards each other with velocities 15 Km/hr and 20 Km/hr, respectively. At the same time, a fly that was sitting on A starts flying towards B with a velocity of 30 Km/hr. As soon as the fly reaches B it immediately turns around and flies towards A, and so on until A and B meet.

    a) What will the displacement of the two cyclists and the fly be when all three meet?

    b) What will be the distance travelled by the fly?

    2. Relevant equations

    x = ut + 0.5at^2
    v^2 = u^2 + 2as
    v= at+u

    3. The attempt at a solution

    attempted a method of graphing but failed and attempted fill in variables in equations but failed again
  2. jcsd
  3. Oct 11, 2008 #2
    There is no acceleration in this problem. The two cyclists move with constant velocities.
    Try to find out when will they meet. The equations of motions are just
    with the distances measured from A and B respectively.
    What is d1+d2 when they meet?
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