Which physical quantity is defined as the rate of change of velocity?

The rate of change of velocity is defined as acceleration. In physics, acceleration measures how quickly an object's velocity changes over time. It can occur due to an increase or decrease in speed or a change in direction.

Acceleration is quantified as the change in velocity divided by the time interval during which the change occurs, typically expressed in meters per second squared (m/s²). For example, if a car increases its speed from 20 m/s to 30 m/s in 5 seconds, the acceleration would be (30 m/s - 20 m/s)/5 s = 2 m/s². This demonstrates how acceleration is fundamentally linked to changes in velocity.

The other choices represent different concepts: displacement refers to the change in position of an object, momentum describes the quantity of motion that an object has, often related to both mass and velocity, and force is an interaction that can cause an object to accelerate. Each of these quantities plays a crucial role in biomechanics and physics, but when specifically considering the rate of change of velocity, acceleration is the correct term to use.