Here's why:
* Net Force: The overall effect of multiple forces acting on an object is determined by the net force. This is the vector sum of all the forces.
* Direction of Acceleration: An object accelerates in the direction of the net force.
* Larger Force Wins: When forces are in opposite directions, the net force is the difference between the two forces. The direction of the net force (and therefore the acceleration) will be in the direction of the stronger force.
Example:
Imagine you push a box to the right with a force of 10 Newtons, and someone else pushes it to the left with a force of 5 Newtons. The net force is 5 Newtons to the right (10 N - 5 N = 5 N). The box will accelerate to the right, in the direction of the larger force.
