Speed is how fast something is travelling.

If you are travelling at a speed you possess movement energy. The scientific term for this is kinetic energy. The faster you go the more kinetic energy you have. If you are stationary you have no kinetic energy.

Speed is the ratio of the distance travelled to the time taken and is usually measured in metres per second (m/s).

It is distance in metres divided by time in seconds.



It is always an average speed that we measure.

Even quite a sophisticated instrument designed to show 'instantaneous speed' works out an average speed, but to be classed as being able to read instantaneous speed it needs to be able to work out how far the object travels in a very short time period indeed - measured in microseconds.

In science lessons we usually work out an average speed for a given time period such as a minute, because the error in measuring smaller time periods would be too great.

Copy and complete the table below.

Use a ruler to draw the borderlines.

You may use your calculator to work out the speeds.


Linked pages: 

Speed experiments

Speed questions