A 20N cart is being pulled to the right with an applied force of 20N at an angle of 40°. The normal force on the cart is 7N and the friction is 3N. Draw the free body diagram. What is the net force in the x and y direction of the cart?

 F_{net-x} = 12.32 N ,   F_{net-x} = -0.14 N  

Explanation:

For this case we apply Newton's second law on each axis,  see attachment

X axis

       F cos 40 - fr = m a

Y Axis  

      F sin 40 +N - W = 0

the net force is

X axis

      = F - fr

     F_{net-x} = 20 cos 40 - 3

     F_{net-x} = 12.32 N

Y Axis  

     F_{net-y} = F sin 40 + N - W

     F_{net-x} = 20 sin 40 + 7 - 20

     F_{net-x} = -0.14 N

we see that the force in this axis is approximately zero