Velocity-time graphs show how the velocity (or speed) of a moving object changes with time. These graphs also show if the object is moving at a constant speed or accelerating, decelerating, or still.

The speed of an object does not require a direction to be considered, it simply has a value and unit, for example, 27 \(m\,s^{-1}\). Velocity is a vector quantity which requires a value, unit and ...

With gold medals in three sprinting events at three Olympic Games, Usain Bolt has written himself into the record books as arguably the fastest human of all time. But just how fast is the Jamaican ...