Velocity
* Definition: Velocity is the rate of change of an object's position. It tells you how fast an object is moving *and* in what direction.
* Zero Velocity: An object at rest has a velocity of zero. This means it's not changing its position. Think of a parked car.
* Example: A car stopped at a red light has zero velocity.
Acceleration
* Definition: Acceleration is the rate of change of an object's velocity. It tells you how quickly the velocity of an object is changing.
* Zero Acceleration: An object with zero acceleration is not changing its velocity. This means it's either moving at a constant speed in a straight line (constant velocity) or it's at rest.
* Example: A car driving at a constant 60 mph on a straight highway has zero acceleration.
Key Differences
* State vs. Change: Velocity describes an object's *state* of motion (how fast and in what direction it's moving), while acceleration describes the *change* in its motion (how quickly its velocity is changing).
* Constant vs. Changing Velocity: Zero acceleration means the velocity is *constant*. Zero velocity means the object is *not moving*.
Analogy
Imagine a car:
* Zero Velocity: The car is parked, not moving.
* Zero Acceleration: The car is driving at a steady 50 mph on a straight road. It's not speeding up or slowing down.
In summary:
* Zero velocity means the object is stationary.
* Zero acceleration means the object's velocity is not changing, regardless of whether it's at rest or moving at a constant speed.
