Find the size of force acting on the body

[sese]

Homework Statement

One body whit m=50kg is pulled whit a acceleration a=2m/s² on an horizontal plane whit an unknow force F which is making whit the plane an angle of 30 degree
The friction coeficient between the body and plane is $$\mu$$=0.2.Find the size of the force F.

m=50kg
a=2m/s²
$$\mu$$=0.2
$$\alpha$$=30

I need to find the size of force acting on the body

http://img11.imageshack.us/img11/7561/61868200.png"

Homework Equations

The Attempt at a Solution

Well i tried to calculate the force whit Newton's formula F=m*a;
Then whit force compontents on Ox,Oy
Oy:N-G-Fy=0
Ox:F_f-Fx=m*a

But my question is "size of force acting on the body" is Fx?!or Fy?!

 

[rl.bhat]

Please post the full text of the problem.

 

[Borek]

But my question is "size of force acting on the body" is Fx?!or Fy?!

Resultant.