- Joined
- May 10, 2013
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What is the acceleration of an 80-kg skier going down the track if θ = 45°?
A. 6.9 m/s^2
B. 9.8 m/s^2
C. 13.9 m/s^2
D. 80 m/s^2
What seems to be tricking me up is that I don't know where a "acceleration" should go.
So if the skier is on an incline the force of gravity will be acting on it equivalent to mg. I also know the skier will be moving parallel to the incline plane with a normal force equivalent to mgsin45. I substitute mgsin45 for masin45 where a is the acceleration and setting the 2 equations equal to each other I get mg = masin45.
Solving for a equals approx 14, answer choice C. How do I know that equation should be rewritten as ma = mgsin45 instead in order to yield the correct answer A?
A. 6.9 m/s^2
B. 9.8 m/s^2
C. 13.9 m/s^2
D. 80 m/s^2
What seems to be tricking me up is that I don't know where a "acceleration" should go.
So if the skier is on an incline the force of gravity will be acting on it equivalent to mg. I also know the skier will be moving parallel to the incline plane with a normal force equivalent to mgsin45. I substitute mgsin45 for masin45 where a is the acceleration and setting the 2 equations equal to each other I get mg = masin45.
Solving for a equals approx 14, answer choice C. How do I know that equation should be rewritten as ma = mgsin45 instead in order to yield the correct answer A?