Which law states that for every action there is an equal and opposite reaction?

Which law states that for every action there is an equal and opposite reaction?

• A. Newton's First Law
• B. Newton's Third Law
• C. Newton's Second Law
• D. Law of Conservation of Energy

Answer: (B)

Two interacting objects exchange forces that are equal in magnitude and opposite in direction. This is Newton's Third Law: for every action, there is an equal and opposite reaction. The forces act on different objects, so they don’t cancel each other and can cause motion changes—for example, you push against a wall and the wall pushes back with the same force, or a rocket moves forward as exhaust is pushed backward. The other laws describe different ideas: inertia (how motion persists unless a net force acts), F = ma (how net force causes acceleration), and energy conservation (how energy is conserved, not how forces pair up).

Two interacting objects exchange forces that are equal in magnitude and opposite in direction. This is Newton's Third Law: for every action, there is an equal and opposite reaction. The forces act on different objects, so they don’t cancel each other and can cause motion changes—for example, you push against a wall and the wall pushes back with the same force, or a rocket moves forward as exhaust is pushed backward. The other laws describe different ideas: inertia (how motion persists unless a net force acts), F = ma (how net force causes acceleration), and energy conservation (how energy is conserved, not how forces pair up).