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Homework Statement
A sled and its rider have a mass of 90 kg and a speed of 3 m/s at point A on the frictionless hill of Figure 5.25. At the bottom of the hill, the sled moves onto a rough surface with a coefficient of friction of .6. How far from the base of the hill will the sled move before stopping?
Homework Equations
KEf + PEf = KEi + PEi
V^2= Vo^2  2ax
KE= 1/2m(v^2)
PE= mgy
The Attempt at a Solution
What I attempted to do was to find the speed at the end of the ramp by using the formula
KEf + PEf = KEi + PEi
so
1/2(90)(9.8)((3)^2) + (90)(9.8)(3) = 1/2m(v^2)
v= 7.67
Then I used the velocity to find the total distance by using the formlula V^2= Vo^2  2ax
so
0 = 60.2176  2(54)(x)
// I got 54 by multiplying the coefficient of friction by the normal force//
when you solve for x you get .56 m. The real answer is 5.77 m
Homework Statement
Homework Equations
The Attempt at a Solution
Attachments

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