In the science of motion (kinematics) speed is defined as the rate of velocity in which an object changes it’s position. To calculate average speed, we use the simple equation:

### Speed= distance / time

Speed is frequently measured in meters per second in science, but various countries which are finely attuned to their automobiles and have an affinity for speed often use miles or kilometers per hour.

In those pictures, our 110cm long school tables provided a perfect pitch for various school items and materials from the science lab to roll down.

Using handheld stopwatches, we timed how long the items took to roll/slide down the table.

i.e. Alexis slid a pen down the 110cm table and it reached the end at an average time of 2.38 secs after 15 trials. Alexis then had the proper components to calculate the pen’s speed. He first converted 110cm to 1.1 meters, then divided it by the average time (2.38 secs).

1.1 m / 2.38 sec = .46 m/s

Practice:
What is the speed of Tim’s ball rolling down a 140 cm table with an average time of 3.12 secs?

Greyhound dogs can run 291.6 meters in 15 secs. What is their speed in meters per second?

*Husain Bolt, the fastest man on the planet, can run 1490.4 meters in 2 minutes, what is his speed? (Remember, it needs to be in m/s)