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.

In physics the word "acceleration" includes the meaning deceleration where the direction of the acceleration is opposite to the direction of the velocity.

Speed-time graphs show speed on the vertical axis and time on the horizontal axis. The gradient of a speed-time graph represents acceleration because: gradient = \( \frac {\text{change in ...