Calculating Net Force and Speed on a Skier: Ramp Problem Explained

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The discussion revolves around calculating the net force and speed of a skier descending a slope with a 35-degree angle, a mass of 70 kg, and a coefficient of kinetic friction of 0.15. The user presents a free-body diagram and calculations for gravitational force and kinetic friction, arriving at a net force of -583.8 N and an acceleration of -8.34 m/s². The user questions the relevance of the ramp's length in their calculations. Responses indicate that the questions were moved to a homework forum for better visibility and that patience is needed due to high traffic. The thread highlights the importance of understanding net force and acceleration in physics problems involving friction.
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The Question is:

A skier goes down a slope with an angle of 35 degrees relative to the horizontal. Her
mass, including all equipment, is 70 kg. The coefficient of kinetic friction between her
skies and the snow is 0.15.
A. Please draw a free-body diagram of the skier.
B. Calculate the net force acting on the skier.
C. If the slope is 60 m long, what is her speed at the bottom of the slope,
assuming that she started from rest?

Does this like correct? (Especially B and C, seeing as I have never done this type before)

My A is:
http://img88.imageshack.us/img88/1207/freend1.th.png

My B is:
Fg=-mg
Fg=-70(9.81)
Fg=-686.7 N

Fk= \muFg
Fk= .15 (-686)
Fk = -102.9 N

Net Force: -686.7 - -102.9= -583.8 NC.) (The length of the ramp dosn't really matter does it?)
F=MA
-583.8= 70A
-8.34 m/s^2 =A

Thanks!
 
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Why isn't anyone answering did I post it wrong or something?
 
These questions belong in the homework forums, where I have just moved your posts. (check your private messages) Also, please be patient, as we have a lot of homework questions coming in right now.
 
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