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physicsss
Sep6-04, 03:29 PM
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?

Atheist
Sep6-04, 07:01 PM
>> ... am I wrong because I put in the negative sign?

yes

faust9
Sep6-04, 07:52 PM
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.