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notallthere

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## Homework Statement

Bob is pulling a sled up a 50 degree hill (meaning the incline is at an angle of

fifty degrees above the horizontal). Sitting on the sled is Bob's niece (unknown

mass). After pulling the sled 30.0 meters up the incline, Bob slips and falls

releasing the rope attached to the sled. The sled (starting from rest) starts sliding down

the incline. After traveling the 30.0 meters down the hill, the sled travels 50.0 meters on

a wide open horizontal surface before finally coming to a stop. Assuming the coefficient

of kinetic friction is the same throughout the entire problem (hill and level ground), find

the coefficient of kinetic friction. If the coefficient of static friction between the sled and

the ground was twice the coefficient of kinetic friction, would the sled move at all?

Hint #1: Treat this as two different parts with two different coordinate systems

(Part 1- on the hill Part 2- on the level ground)

Hint #2: The speed that the sled reaches at the bottom of the hill is the same speed the

sled starts with when traveling on the level ground.

## Homework Equations

F=ma Ff=μFn Fgx=mgsinθ Fgy=mgcosθ Δx=viΔt+(1/2)aΔt^2 vf^2=vi^2+2aΔx Δx=vfΔt-(1/2)aΔt^2 vf=vi+aΔt Δx=(1/2)(Vi+Vf)Δt

and any other equation that could be used to solve this problem

(kinematic and force equations)

## The Attempt at a Solution

I have no clue on how to solve this problem, and any help would be greatly appreciated