The rate of change of velocity is called:

The correct answer is acceleration, which is defined as the rate of change of velocity over time. In physics, acceleration quantifies how quickly an object is speeding up, slowing down, or changing direction. It is a vector quantity, meaning it has both a magnitude and a direction, and is typically measured in meters per second squared (m/s²).

To understand its importance, consider that when an object experiences a change in velocity, it must be due to some form of net force acting upon it, as described by Newton's second law of motion. Acceleration plays a crucial role in determining how quickly an object will reach a certain speed or how its motion will change in response to forces acting on it.

The other options do not accurately represent the concept of the rate of change of velocity. Mass refers to the amount of matter in an object, force is an influence that can cause an object to change its velocity, and weight is the gravitational force acting on an object's mass. These concepts relate to mechanics but do not specifically address the change in velocity itself, which is why acceleration is the correct choice.