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Homework Help: Newton's Second Law

  1. Oct 18, 2005 #1
    Three astronauts, propelled by jetpacks, push a 120kg asteroid toward a processing dock, exerting the forces
    F1 = 32N at 30 degrees above the horizontal
    F2 = 55N on the horizontal
    F3 = 41N below 60 degrees below the horizontal

    what is the asteroids acceleration in unit vector notation?

    m = 120kg
    F2 = (5N)i

    F1+F2+F3 = ma

    F1 = (32N cos30deg) , (32N sin30deg)
    F1 = (27.7)i + 16j

    F3 = (41N cos-60deg) , (41N sin-60deg)
    F3 = (20.5N)i - (35.5N)j

    Fnet = ma
    Fnet/m = a
    (27.7/120 +55 + 20.5/120)i , (-35.5/120 + 16/120)j = a

    Is this right so far?
    Last edited: Oct 18, 2005
  2. jcsd
  3. Oct 18, 2005 #2


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    Homework Helper

    Apart from a couple of typos, yes it's correct.
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