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## Homework Statement

A 25.6-kg boy pulls a 4.81-kg toboggan up a hill inclined at 25.7º to the horizontal. The vertical height of the hill is 27.3 m and the coefficient of friction of the hill surface is 0.4

a) Determine how much work the boy must apply on the toboggan to pull it at a constant velocity up the hill? (Hint: An FBD is needed to see all your forces acting on te toboggan)

## Homework Equations

W = F x ∆d

Eg = mgh

Ek = 0.5mv^2

vf^2 - vi^2 = 2a∆d

## The Attempt at a Solution

[tex]-mgsin25.7º - \mu Kmgcos25.7º = m * a[/tex]

[tex]-(30.41 x 9.8 x sin 25.7º) - (.4 x 30.41 x 9.8 x cos 25.7) = 30.41 * a[/tex]

[tex]-129.24 - 106.46 = 30.41a[/tex]

[tex]a = -7.75 m/s^2[/tex]

Calculating length of the hill:

[tex]\frac{27.3}{sin25.7º} = 62.95m[/tex]

I don't really know what to do after this.