Newton's Third Law: Action-Reaction Force Pairs

Steps:

• Recall Newton's third law: every action force has an equal and opposite reaction force acting on a different object.
• Identify action-reaction pairs as forces of equal magnitude but opposite direction between two interacting objects.
• Check each option: true third-law pairs act on separate bodies, not the same one.
• Select the option where forces are mutual attractions or pushes between distinct objects.

Why B is correct:

• The Earth-Moon gravitational forces are equal in magnitude, opposite in direction, and act on different bodies (Earth pulls Moon, Moon pulls Earth), directly matching Newton's third law definition of action-reaction pairs.

Why the others are wrong:

• A: Resistive and driving forces both act on the car, so they balance but are not a third-law pair.
• C: Support and weight both act on the box, making them concurrent forces on one object.
• D: Lift and weight both act on the airplane, so they are not mutual action-reaction forces.

Final answer: B