Kinematics and Kinetics in Human Movement Practice Test

The key idea here is action–reaction pairs. When one object pushes or pulls on another, the second object pushes or pulls back with the same magnitude but in the opposite direction, and both forces act on different objects at the same time. This is why pushing against a wall feels like the wall is pushing you back with the same strength, or why you move backward slightly when you push off the ground to jump.

The statement that captures this is the one that says the forces are equal in magnitude and opposite in direction, acting on two different bodies. It’s not about momentum or energy conservation, which describe other principles of how motion and energy behave in systems, and it’s not that the reaction would point in the same direction as the action.