Which Newtonian law states that the force on an object equals its mass multiplied by its acceleration?

Which Newtonian law states that the force on an object equals its mass multiplied by its acceleration?

• A. Newton's Second Law of Motion
• B. Newton's Third Law of Motion
• C. The Law of Inertia
• D. Law of Universal Gravitation

Answer: (A)

Net force determines acceleration. The statement that the force on an object equals its mass times its acceleration expresses Newton's second law: F_net = m a. Mass acts as the resistance to changes in motion, so for a given mass the acceleration is proportional to the net force and points in the same direction as that force. If you double the net force on a 3 kg object, its acceleration doubles; if you double the mass with the same net force, the acceleration halves. The equation is vectorial: the net force and the acceleration share direction, mass is a scalar, and acceleration is a vector. This best captures how force, mass, and motion are linked. The law of inertia describes motion without net force, Newton's third law describes action-reaction pairs, and the law of universal gravitation explains how masses attract each other, but none express the direct F = m a relationship.

Net force determines acceleration. The statement that the force on an object equals its mass times its acceleration expresses Newton's second law: F_net = m a. Mass acts as the resistance to changes in motion, so for a given mass the acceleration is proportional to the net force and points in the same direction as that force. If you double the net force on a 3 kg object, its acceleration doubles; if you double the mass with the same net force, the acceleration halves. The equation is vectorial: the net force and the acceleration share direction, mass is a scalar, and acceleration is a vector.

This best captures how force, mass, and motion are linked. The law of inertia describes motion without net force, Newton's third law describes action-reaction pairs, and the law of universal gravitation explains how masses attract each other, but none express the direct F = m a relationship.