North Carolina Basic Law Enforcement Training (BLET) State Practice Exam

According to the laws of motion, what relationship exists between force, mass, and acceleration?

1. Acceleration is inversely proportional to force

2. Force is equal to mass times acceleration

3. Mass is directly proportional to acceleration

4. Acceleration does not depend on mass

The correct answer is: Force is equal to mass times acceleration

The correct choice highlights Newton's second law of motion, which states that the force acting on an object is equal to the mass of that object multiplied by its acceleration. This fundamental principle can be expressed mathematically as F = ma, where F represents force, m represents mass, and a represents acceleration. This relationship demonstrates that for a constant mass, any change in force will result in a proportional change in acceleration. Thus, if you increase the mass while applying a constant force, the acceleration will decrease, and vice versa. This principle is crucial in understanding how objects respond to applied forces, making it a cornerstone of the study of dynamics in physics. In contrast to this, the other options misrepresent the relationships between these physical quantities. For example, stating that acceleration is inversely proportional to force implies that increasing force would decrease acceleration, which contradicts the established principle. Furthermore, mass being directly proportional to acceleration does not hold without considering the force—acceleration depends on force when mass is constant. Similarly, stating that acceleration does not depend on mass neglects the important interplay between these factors as outlined by Newton's second law.