for driving is the time between noticing a hazard and taking an action to deal with it

is the distance a vehicle travels while a driver reacts; the vehicle does not slow during this time

is the distance a vehicle travels between the brakes being applied and the vehicle coming to a stop

is the sum of the thinking and braking distances

Stopping

Combined science

Newton’s Third Law (with free body diagrams in 2D)

Resultant forces and their effects

Forces in two dimensions (including resolution of a force)

Force, mass and acceleration (a = (v – u)/t)

Newton's Second Law (including inertia)

Conservation of momentum

Changing momentum

Stopping safely

In the Gravity in space unit, they will build on this knowledge to learn about centripetal forces, orbital motion, stellar evolution, red shift and the big bang.

In the Energy of moving objects unit, pupils learnt how to calculate the amount of energy of objects have because they are moving, stretched or in a gravitational field; and to calculate energy transfers using knowledge of energy conservation and dissipation.

This unit explores forces, interactions, and Newton’s laws, including motion, rotation, and momentum. It covers reaction times, stopping distances, and deceleration dangers. Emphasis is on force diagrams, calculations, experiments, and evaluating methods for accuracy and safety.

Forces make things change

Physical activity and equipment requiring safe use

time between noticing a hazard and taking an action to deal with it

distance a vehicle travels during the time a driver takes to react

distance a vehicle travels before stopping after brakes are pressed

sum of the thinking and braking distances

Match the following key terms to their definitions.

to the chemical store, increasing the amount of fuel

to the thermal store, heating the engine 

to the gravitational store, raising the vehicle up a hill

Where is most of the energy from the kinetic store transferred to when a vehicle brakes and slows down?

Which of the following factors affect both the thinking distance and the braking distance of a vehicle?

A driver with a reaction time of 1.2 s is travelling at 30 m/s along a road.
Calculate the thinking distance for this driver. Give the correct unit.

The driver of a lorry travelling at 12.0 m/s notices a hazard. The driver's reaction time is 0.80 s and, at this speed, the braking distance of the lorry is 25.0 m. 
Calculate the stopping distance.

A car is travelling at 30 m/s and, at this speed, its braking distance is 75 m.
Calculate the minimum reaction time needed to stop the car in less than 90 m. Give the correct unit.

Which force is caused by two solid surfaces moving across each other?

When a vehicle increases its speed, it is accelerating and when it decreases its speed, it is {{}}.

the size of the forward force is increasing

there is no forward force acting on the trolley

a frictional force acts in the direction opposite to the movement

a drag force acts in the direction opposite to the movement

The figure shows a dynamics trolley just after it has reached the end of a ramp.
Which of the following statements help explain why the trolley slows down when it has left the ramp?

kinetic energy =  ½ × (mass)$$^2$$ × speed

kinetic energy =  ½ × mass × (speed)$$^2$$

kinetic energy =  ½ × (mass)$$^2$$ × (speed)$$^2$$

Which of the following is the correct equation for calculating the kinetic energy of an object?

A motorcycle is travelling at 9.00 m/s. How far will the motorcycle travel in 1.40 s? 

A motorcycle has a mass of 200 kg and is travelling at 9.00 m/s.
Calculate the kinetic energy of the motorcycle. Give the unit.

Starter Quiz

Which force is caused by two solid surfaces moving across each other?