Speed and velocity are both measurements related to the motion of an object, but they have distinct definitions and implications.
Speed refers to how fast an object is moving, and it is defined as the rate of change of distance. It is a scalar quantity, meaning it only has magnitude and no direction. The formula for speed is:
Speed = Distance / Time
Velocity, on the other hand, refers to the rate of change of displacement. Displacement is the change in position of an object, taking into account both distance and direction. Velocity is a vector quantity because it has both magnitude (speed) and direction. The formula for velocity is:
Velocity = Displacement / Time
So, the key difference between speed and velocity is that speed only considers the magnitude of the motion, whereas velocity takes into account both the magnitude and direction.
Now, if an object is moving at a constant speed, it means that the magnitude of its velocity remains the same over time. However, its velocity can still change if there is a change in direction. For example, if an object moves in a circle at a constant speed, its velocity is constantly changing because the direction is constantly changing.
In summary, while a constant speed implies a constant magnitude of velocity, the velocity itself can still change if there is a change in direction.