1. Stopping distances

2. Forces on the road
For a car travelling at a constant velocity the resultant force is zero.
velocity

3. Changing the velocity
How can the driver change the velocity?

4. How long will it take to stop?
The braking force depends on the speed of the vehicle and the mass of the vehicle
F=ma
At high speeds the deceleration (negative acceleration) is higher so braking force is higher
The greater the mass the greater the braking force

5. Stopping distance Include thinking time and braking time
Highway code talks about 2 seconds to think

7. What affects stopping distance?
Tiredness
Alcohol and drugs
The speed
The road conditions (eg ice and rain)
Poorly maintained vehicles (bald tyres)

8. Your task To design a poster to encourage drivers to be safe
Include some science (F=ma) to back up your argument
You might want to think of your audience and how you will have impact
thinking time
stopping time
mass
force
acceleration
deceleration
brakes
friction
speed