Every day people and vehicles travel at different speeds and are exposed to large accelerations and forces.
What is a typical speed for walking?
What is the typical value for the human reaction time?
Which equation correctly relates stopping distance, braking distance and thinking distance?
Stopping distance = thinking distance × braking distance
Stopping distance = thinking distance + braking distance
Braking distance = stopping distance + thinking distance
Which of these can increase the reaction time of a driver?
Drugs, alcohol or tiredness
The mass of the car
The speed of the car
Which of these factors affect thinking distance but NOT braking distance?
Poor vehicle conditions such as worn tyres or worn brakes
What happens to the thinking distance when the speed of a car doubles?
It stays the same
It increases by a factor of four
Which of these affect the thinking distance and the braking distance of a moving vehicle?
Icy or wet roads
Drugs and alcohol
The speed of the vehicle
The speed of a car doubles from 20 mph to 40 mph. What affect does this have on the braking distance of the car?
It does not change
Why are crumple zones used as car safety features?
They decrease the time over which a car is brought to rest which decreases the force exerted on the passengers
They increase the time over which a car is brought to rest which decreases the force exerted on the passengers
They allow the forces on the passengers to be as large as possible
What is the force needed to accelerate a small lorry to its top speed on a single carriageway? Use 2,500 kg for the mass of the lorry and 3 m/s2 for the acceleration.