Which statement best describes a situation where acceleration is zero?

Which statement best describes a situation where acceleration is zero?

• A. The velocity is changing
• B. The net force on the object is nonzero
• C. The object has zero mass
• D. The net force on the object is zero

Answer: (D)

Acceleration is how quickly velocity changes. When acceleration is zero, velocity isn’t changing, so an object at rest stays at rest or an object in motion keeps a constant velocity in a straight line. Newton’s second law ties acceleration to net force: a = F_net / m. For an object with mass, zero acceleration occurs exactly when the net force is zero. That means there is no unbalanced push or pull acting on the object, so its motion remains constant. The other ideas describe situations with changing velocity or a nonzero net force, which would produce acceleration. The idea of zero mass isn’t part of this simple relation in standard mechanics, so it’s not relevant to the typical scenario.

Acceleration is how quickly velocity changes. When acceleration is zero, velocity isn’t changing, so an object at rest stays at rest or an object in motion keeps a constant velocity in a straight line. Newton’s second law ties acceleration to net force: a = F_net / m. For an object with mass, zero acceleration occurs exactly when the net force is zero. That means there is no unbalanced push or pull acting on the object, so its motion remains constant. The other ideas describe situations with changing velocity or a nonzero net force, which would produce acceleration. The idea of zero mass isn’t part of this simple relation in standard mechanics, so it’s not relevant to the typical scenario.