- #1
Sandy_221
- 5
- 0
THE QUESTION IS THIS:
A skier of mass 55.0 kg slides down a slope 11.7 m long, inclined at an angle f to the horizontal. The magnitude of the kinetic friction is 41.5 N. The skier’s initial speed is 65.7 cm/s and the speed at the bottom of the slope is 7.19 m/s. Determine the angle f from the law of conservation of energy. Air resistance is negligible.
I know the answer to this question. What I don't understand though is why is it that we don't use the vertical component of velocity here (or in any other conservation of energy for that matter) when calculating 1/2 v1 squared and 1/2 v2 squared . I mean why aren't you supposed to take the vertical components of velocity for both v1 and v2, but only use their own values. Whereas for the height in calculating the poential energy you do.
This is kind of bugging me. So, I appreciate your thorough response everyone!
Sandy
A skier of mass 55.0 kg slides down a slope 11.7 m long, inclined at an angle f to the horizontal. The magnitude of the kinetic friction is 41.5 N. The skier’s initial speed is 65.7 cm/s and the speed at the bottom of the slope is 7.19 m/s. Determine the angle f from the law of conservation of energy. Air resistance is negligible.
I know the answer to this question. What I don't understand though is why is it that we don't use the vertical component of velocity here (or in any other conservation of energy for that matter) when calculating 1/2 v1 squared and 1/2 v2 squared . I mean why aren't you supposed to take the vertical components of velocity for both v1 and v2, but only use their own values. Whereas for the height in calculating the poential energy you do.
This is kind of bugging me. So, I appreciate your thorough response everyone!
Sandy