Q. Observation 1: Try to stop a ball coming towards you,so as to save a boundary, by applying a force of some magnitude in the opposite direction of the motion of ball.
Observation 2: In this case apply the force of same magnitude but in same direction of the motion of the ball.
In observation 1 boy saves a boundary by applying a force opposite to the direction of motion but in observation 2, the change in direction of force cost the team 4 runs as the change in direction of force pushed the ball further to the boundary.
So, the change in effect of a force can be experienced by a change in it's direction as well as magnitude. The above statement is :-