We will discuss about the force on a moving body.
What else can a force do, besides moving an object?
It can stop a moving object
It can change the direction of a moving object
It can also change the shape of an object
If we hit a ball, it begins to move on the floor in a certain direction. If anyone tries to stop it, he applies force with his leg or hand against the direction of its movement.
If a boy rolls a big ball in any direction on the floor and another boy applies force on the ball in its moving direction with his leg, the ball begins to move faster.
Thus for stopping a moving ball we need to apply force on the ball against its direction of movement or in the opposite direction. If we want the ball to move faster, the force is applied in the direction it is already moving.