(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

http://i450.photobucket.com/albums/qq230/JJBladester/06_p51.jpg?t=1223753179

The 2.0kg wood box in the figure slides down a vertical wood wall while you push on it at a 45 degree angle.

What magnitude of force should you apply to cause the box to slide down at a constant speed?

2. Relevant equations

I am having a hard time figuring out the normal force in this problem.

I have set the problem up with four forces (f_k (friction), F_g (gravity), n (normal), F_push (push)). I got the coefficient of friction (f_k) as 0.20 from my textbook.

Fnet(x) = F_push(x) + F_g(x) + n + f_k(x)

Fnet(x) = F_push*cos(45) + 0 + n + 0

Fnet(y) = F_push(y) + F_g(y) + f_k(y)

Fnet(y) = F_push*sin(45) + (2.0)(9.8) -[0.20*2.0*(sin(45)]

3. The attempt at a solution

I know that the normal force acts perpendicular to the surface, so their should be no n in the y-direction. I'm stuck in finding the normal force in the x-direction and I believe this is the missing link in me figuring out this problem.

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# Homework Help: Dynamic Equilibrium Question (block sliding on wall)

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