This resource allows students to investigate the braking efficiency of cars and trucks by testing stopping distances under conditions they partially control. The simulation can be used to compare effects of vehicle type, tyres, road surface and weather conditions. Student can choose their driving speed in different conditions, then apply the brakes and compare stopping distances. They can make predictions and investigate relationships between friction, tyre type or driver fatigue and stopping distances.
Adapting the resource
First, allow students to explore the interactive and ask them to take particular notice of the many variables.Now encourage them to make specific predictions about stopping distances under different combinations of conditions and gather evidence to support or refute these. As well as thinking about which variables to alter they will need to think about which ones to keep the same. There are many possible predictions, some more complex than others. Examples could be:
- All vehicles will take a longer stopping distance if their tyres are bald.
- The loaded truck will go further than any other vehicle when it brakes, at any driving speed.
- Doubling the speed of any vehicle will more than double its stopping distance.
If students claim a prediction they made is correct, they should be able to back this up with data. This means they will need to devise ways of systematically collecting data from each trial that they run during their investigation.