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Homework Help: Vectors again

  1. Sep 6, 2004 #1
    a skier is accelerating down a 30.0 degrees hill at 3.10 m/s^2. What is the vertical component of her acceleration?

    I did 3.10 m/s^2 *sin(30) and got -1.55 m/s^2, but as usual, my answer is wrong.... :cry: The box for the answer looks like this: ____m/s2 (downward)... am I wrong because I put in the negative sign?
     
    Last edited: Sep 6, 2004
  2. jcsd
  3. Sep 6, 2004 #2
    >> ... am I wrong because I put in the negative sign?

    yes
     
  4. Sep 6, 2004 #3
    To expound a little. Yes because the question defined (+) to be downward when it said "accelerating down a 30.0 degrees hill at 3.10 m/s^2". By making your answer (-) you are sying the skier is accelerating in the direction opposite to the defined positive direction--the skier is accelerating upward.
     
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