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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
    d1=v1*t
    d2=v2*t
    with the distances measured from A and B respectively.
    What is d1+d2 when they meet?
     
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