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beamerrox
Jan28-09, 04:47 PM
1. The problem statement, all variables and given/known data
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


2. Relevant 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.


3. 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??

Hannisch
Jan28-09, 05:08 PM
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?