What demonstrates the effects of different strengths or directions of pushes and pulls on motion?

The best demonstration of the effects of different strengths or directions of pushes and pulls on motion is stopping a rolling ball or observing two objects in collision. This scenario clearly illustrates how various forces can alter the state of motion of objects. When a rolling ball is stopped, the force applied to it counteracts its motion, showcasing how a push (in this case, a force opposing the ball's direction) can change its velocity and eventually bring it to rest.

Additionally, watching two objects collide allows one to observe how forces are transmitted during the impact. The strength of the push or pull during the collision will determine the resulting motion of both objects after the collision, illustrating principles of momentum and energy transfer. In essence, this scenario provides clear examples of how force influences motion, both in magnitude and direction, making it an ideal choice for demonstrating these concepts.