Question 20

For every action, there is a simultaneous equal and opposite reaction.

Newton's Third Law of Motion states that for every action, there is an equal and opposite reaction. This principle highlights the interaction between two objects, where the force exerted by one object results in a force of the same magnitude but in the opposite direction exerted by the second object.

A) For every action, there is a simultaneous equal and opposite reaction.

This statement accurately encapsulates the essence of Newton's Third Law of Motion. It emphasizes that forces always occur in pairs, demonstrating the reciprocity of interactions between objects.

B) The net force acting on an object is the product of the object's mass and acceleration.

This statement is a restatement of Newton's Second Law of Motion, which relates to how forces affect motion rather than the interaction between two objects. It is not relevant to summarizing Newton's Third Law.

C) The acceleration of any object is limited by the localized gravitational force.

This statement does not convey the principle of Newton's Third Law; instead, it suggests limitations on acceleration due to gravity. It pertains to gravitational effects rather than the reaction forces defined by Newton's Third Law.

D) An object maintains its state of motion unless acted upon by an unbalanced force.

This statement describes Newton's First Law of Motion, focusing on inertia and the conditions required for an object to change its state of motion. It does not summarize the action-reaction relationship posited by Newton's Third Law.

Conclusion

The correct answer, A, clearly defines Newton's Third Law of Motion and its fundamental principle of action and reaction. Options B, C, and D refer to different laws or principles in physics, failing to capture the specific interaction aspect emphasized by Newton's Third Law. Thus, A stands out as the definitive summary of the law in question.