The relationship between force, mass, and acceleration is described by which law?

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

Answer: (B)

The central idea is that the motion of a body under a net external force is governed by F = ma: the acceleration produced is proportional to the net force and inversely proportional to the mass. This means that for a fixed mass, increasing the force increases acceleration in direct proportion, while for a fixed force, increasing the mass reduces acceleration. The acceleration points in the same direction as the net force. That’s why heavier objects accelerate less under the same push, and why a bigger push makes a lighter object accelerate more. This is Newton's second law of motion. The first law is about motion without any net force, the third law is about action–reaction pairs, and the momentum conservation law deals with how momentum behaves in collisions, not the direct F = ma relationship.