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Finding net force

  1. Oct 3, 2008 #1
    The position of a 2.5x10^5N training helicopter under test is given by
    r=(0.020m/s^3)t^3i + (2.2m/s)tj-(0.060m/s^2)t^2k , find the net force of the helicopter at t=5.0s

    express F in the form Fx Fy and Fz

    F=ma F=Fx+Fy+Fz

    so far i plugged in t to each component to get 2.5m, 11m, and 1.5 m,
    now i just need to know how to use the force that is given to find the x, y, and z components. need a little guidance.
  2. jcsd
  3. Oct 3, 2008 #2

    Doc Al

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    Staff: Mentor

    The net force is not given, you have to figure it out. What does Newton's 2nd law say about net force? (That should give you a hint about what you need to do.)
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