Here's why:
* Speed is the rate at which an object moves. It tells you how fast the object is going.
* Direction tells you which way the object is moving.
* Velocity is a combination of both speed and direction. It's a vector quantity, meaning it has both magnitude (speed) and direction.
Example:
* A car traveling at a constant speed of 60 mph in a straight line has a constant velocity.
* A car traveling at a constant speed of 60 mph but changing direction (e.g., turning a corner) does not have a constant velocity.
Key takeaway: Velocity is only constant if both the speed and direction of motion remain unchanged.
