Vectors again

1. Sep 6, 2004

physicsss

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.... 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. Sep 6, 2004

Atheist

>> ... am I wrong because I put in the negative sign?

yes

3. Sep 6, 2004

faust9

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.