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## Homework Statement

They're two boxes connected on a pulley, each weighing 2 kg. Box 1 is on a 30 degree incline and box 2 is on a 60 degree incline.

a. Find the acceleration ignoring friction

b. Find the acceleration if the coefficient of kinetic friction is 0.1.

## Homework Equations

F=ma

F

_{fr}=u

_{k}F

_{N}

## The Attempt at a Solution

I drew the free-body diagram. We are missing the pulling of pushing force (F

_{p}), the tension force and the acceleration (which we are trying to find).

So this what I did for part a (ignoring friction):

BOX 1-

- ∑F

_{x1}=F

_{p}+mgsinΘ-F

_{T}=m

_{1}a

_{1}

- F

_{t}=F

_{p}+ mgsinΘ - m

_{1}a

_{1}

I solved for tension force since we don't have that.

BOX 2-

- ∑F

_{x2}=F

_{p}-mgsinΘ+F

_{T}=m

_{2}a

_{2}

I substituted the equation from Box 1 for F

_{t}so I could eliminate it.

- F

_{p}+F

_{p}+mgsinΘ-mgsinΘ - m

_{1}a

_{1}=m

_{2}a

_{2}

- 2F

_{p}/m

_{1}m

_{2}=a

So I am left with F

_{p}still, which we don't know. I am confused.

For part b, with coefficient of kinetic friction of .1, I did the same thing but I added F

_{fr}for box #2 because I made it so that the pulling force and the tension force were in the same direction while the frictional force would obviously be opposing that. For box #1 I thought that F

_{t}would be like the frictional force since it's opposing force (I made the box going down in #1) so I didn't even add it for that part.

Can you tell me what I am doing wrong.