Which statement describes Newton's Third Law?

Which statement describes Newton's Third Law?

• A. Gravity is the force of attraction between objects.
• B. For every action, there is an equal and opposite reaction.
• C. The total energy in a system is always increasing.
• D. Potential energy only depends on position.

Answer: (B)

When two objects interact, forces come in equal and opposite pairs acting on the two objects involved. This is Newton's Third Law. The forces are the same in strength but opposite in direction, and they act on different bodies, so they don’t cancel each other out. For example, when you push against a wall, the wall pushes back on you with the same force in the opposite direction. Similarly, when you walk, friction with the ground pushes you forward, while you push backward on the ground. In a rocket, gas is expelled backward and the rocket is pushed forward with the same force in the opposite direction. These action–reaction pairs explain a lot of everyday motion and why forces balance differently depending on the masses involved. Other statements describe gravity or energy, which are separate concepts, not the way forces interact in pairs.

When two objects interact, forces come in equal and opposite pairs acting on the two objects involved. This is Newton's Third Law. The forces are the same in strength but opposite in direction, and they act on different bodies, so they don’t cancel each other out. For example, when you push against a wall, the wall pushes back on you with the same force in the opposite direction. Similarly, when you walk, friction with the ground pushes you forward, while you push backward on the ground. In a rocket, gas is expelled backward and the rocket is pushed forward with the same force in the opposite direction.

These action–reaction pairs explain a lot of everyday motion and why forces balance differently depending on the masses involved. Other statements describe gravity or energy, which are separate concepts, not the way forces interact in pairs.