Work Energy: block w/ friction

1. The problem statement, all variables and given/known data
Find the initial speed of a block which travels 10m along a horizontal surface if [tex]\mu[/tex]= 0.40 between the block and the surface before stopping.


2. Relevant equations
[tex]\Sigma[/tex]W = 1/2mvB2 - 1/2mvA2 + mgyB - mgyA

[tex]\Sigma[/tex]W = W * dAB * cos (W, dAB)

f = [tex]\mu[/tex]* N
N= mgsin[tex]\theta[/tex]

3. The attempt at a solution
so far i have:
[tex]\Sigma[/tex]W = 0
[tex]\Sigma[/tex]W = WN + WW + Wf

and

[tex]\Sigma[/tex]W = WW * dAB * cos (270)
[tex]\Sigma[/tex]W = WW * 10m * 0


not sure if i'm doing this right or where to go from here
 
10
0
This problem requires an equation that you haven't included yet.

So we'll start with:
[tex]\Sigma[/tex]F = max
[tex]\Sigma[/tex]F = Px + fx + Nx + Wx
max = Px + fx+ Nx + Wx

[tex]\mu[/tex] = -a / g
Try to solve it from here.
 

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