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Homework Help: Net Force Question with no velocity or time given.

  1. Jan 17, 2008 #1
    [SOLVED] Net Force Question with no velocity or time given.

    1. The problem statement, all variables and given/known data
    A ball of mass 0.6 kg flies through the air at low speed, so that air resistance is negligible.

    What is the net force acting on the ball while it is in motion?

    2. Relevant equations
    Fnet = m(change in velocity/change in time)

    3. The attempt at a solution
    Can't attempt because I don't know how to find the change in velocity or the change in time. They don't tell beginning time or ending time, the tell the weight, and neither the velocity. I know the vector will look like <0, y, 0> but I don't know how to calculate the y value.
  2. jcsd
  3. Jan 17, 2008 #2

    D H

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    Staff Emeritus
    Science Advisor

    You already know you can ignore air resistance. What other forces act on the ball?
  4. Jan 17, 2008 #3
    You have gravity acting on the ball as well, and thats it. The gravity is pulling the ball down in the y direction. Would it be gravity? Or the weight plus gravity?
  5. Jan 17, 2008 #4
    Is gravity -9.8 N? If it is then that should be the answer right?
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