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Homework Help: Newton's 2nd law questions

  1. Jul 12, 2008 #1
    1. The problem statement, all variables and given/known data

    A man walking with aid of a cane approaches a skateboard (mass 3.5 kg) lying on the sidewalkk. Pushing with an angle of 60 down from the horizontal with his cane, he applies a force of 115N, which is enough to roll the skateboard out of the way.
    a) calculate the horizontal force acting on the skateboard
    b) calculate the initial acceleration of the skateboard.

    3. The attempt at a solution
    Fa = ma
    115cos60 = 3.5(a)
    a = 19.3 m/s2
    Fx = 67.55 N.

    My answer was wroung T_T
    what did i miss?
  2. jcsd
  3. Jul 12, 2008 #2
    the setup looks right. did you double check your calculations? i got different answers.

    edit: looks like your calculator is set on gradients, not degrees.
  4. Jul 12, 2008 #3
    yea im pretty sure i did. But the answer is supposed to be 58 N and 16m/s2

    edit : lol i feel like an idiot >< thank you
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