# Chapter 1: Kinematics - Describing Motion

HideShow resource information

Kinematics - Describing Motion

Speed

We can calculate the average speed of something moving if we know the distance it travels and the time it takes with the equation:

Average Speed = Distance divided by time

If the object is moving at a constant speed this equation will give us its speed during the time taken, if the speed is constantly changing it gives us the average speed.

As speed is calculated by distance (m) and time (s) the unit overall for speed is ms -1 although depending on the situation the unit can change.

Determing speed- You can determine the speed of something moving buy looking at the time is takes to travel between two fixed points. However this will not be able to tell you if the car increases/decreases or stays at a constant speed between the points. There are four methods of this;

Using two light gates

As the leading edge of the card breaks the first light gate beam, the timer is started. The timer then stops once the front of the card breaks the second beam at the

## Similar Physics resources:

See all Physics resources »See all Motion resources »