All forces, which act on the object, must be represented in the free-body diagram. A free body diagram only includes the forces that act on the object, not the forces the object itself exerts on other objects. The ball is at rest. The ground must exert a force equal in magnitude and opposite in direction on the ball. This force is called the normal force, n , since it is normal to the surface.
Gravity acts downward.
The component of F g perpendicular to the surface is cancelled out by the normal force the surface exerts on the mass. The mass does not accelerate in the direction perpendicular to the surface. The component of F g parallel to the surface causes the mass to accelerate in that direction. While in flight, gravity and air friction act on the ball. The foot pushes the ball forward, the ball pushes the foot backward.