Help with Newtons laws and friction

AI Thread Summary
The discussion revolves around a physics problem involving a girl skiing down a 35-degree incline with a coefficient of friction of 0.12. Key points include the need to draw a free body diagram (FBD) to analyze the forces acting on her, including gravitational force and friction. Participants emphasize the importance of using sine and cosine functions to resolve the forces in the direction of motion. The equations of motion, particularly ΣF = MA, are highlighted as essential for calculating acceleration and time. The overall focus is on setting up the problem correctly to find the girl's acceleration and the time taken to travel 120 meters.
beamerrox
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Homework Statement


a girl is skiing down a 35 degree inclined hill that is 120 meters long. She starts from rest and the snow has a coefficient of friction of .12.
A. Draw an FBD
B what is her acceleration
c. How much time dows it take her to travel the 120 meters


Homework Equations


I am unsure on how to set up the question solution. I think it's CAE's that are used as well, but i am completely unsure.


The Attempt at a Solution


ΣF= MA
ΣF=9.8(m)
vi= 0m/s
ΛD=120 m
vf = ?
t=?
a=?
120cos35= 98.29?
120sin35= 68.82?

If anyone could please help i would really appreciate it. If i can figure out how to set this problem up and solve it, i will be able to figure the other problems out. Thank you so much!
I don't think there's enough to solve it using cae's can i use the sin and cosine functions with the 35 degrees??
 
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You have to take her direction of motion into consideration. If you've drawn a FBD you see that there's a difference in the direction of the forces that have an effect on her acceleration. If you can take this into consideration?
 

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