Forbes contributors publish independent expert analyses and insights. I help people communicate data clearly with graphs. This article is more than 10 years old. This is the first post in a new ...

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 y}}{\ ...

The area under the graph = the distance travelled. This is a speed-time graph for a car moving between two sets of traffic lights. The rate of change of speed is the slope or gradient of the speed ...