the overall effect of the forces acting on an object

caused by a resultant force and results in a change in speed and/or direction of movement

the amount of matter in an object, measured in kilograms (kg)

Newton's Second Law

Physics

Newton's Third Law

Resultant forces and their effects

Moments, levers and gears

Balancing

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

Stopping (and estimating stopping distances)

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

The overall effect of the forces acting on an object.

A change in velocity caused by a resultant force.

The amount of matter in an object, measured in kilograms (kg).

Match the following key words and phrases to their explanations.

acceleration = change in velocity ÷ time taken

Which of following is a statement of Newton’s Second Law of motion?

A firework rocket of mass 0.20 kg accelerating at 20 m/s$$^2$$.

A bicycle of mass 60 kg accelerating at 3.0 m/s$$^2$$.

A van of mass 1500 kg accelerating .at 0.5 m/s$$^2$$

A motorcycle of mass 200 kg accelerating at 4.0 m/s$$^2$$.

A car of mass 900 kg accelerating at 1.5 m/s$$^2$$.

Starting with the smallest force, sort the following into order of increasing resultant force acting on the objects.

One that accelerates at 4 m/s² when a resultant force of 2 N is acting.

One that accelerates at 2 m/s² when a resultant force of 2 N is acting.

One that accelerates at 2 m/s² when a resultant force of 4 N is acting.

One that accelerates at 4 m/s² when a resultant force of 4 N is acting.

One that accelerates at 0.5 m/s² when a resultant force of 0.5 N is acting.

Which of following objects have a mass of 1 kg?

A spaceship of mass 9000 kg fires its engines and produces a thrust of 1800 N.
Calculate the acceleration of the spaceship. You do not need to give the unit.

A train of mass 75 000 kg travels along horizontal track. The driving force is 40 000 N forwards, the frictional force is 4000 N and the drag force 6000 N. Calculate the acceleration of the train.

Match the following quantities to the correct unit.

The greater the resultant force, the greater the acceleration of an object.

The greater the resultant force, the lower the acceleration of an object.

The greater the mass, the greater the acceleration of an object.

The greater the mass, the lower the acceleration of an object.

Which of the following statements about the acceleration of an object are correct?

Which single word is used to describe slowing down due to a resultant force?

A resultant force of 20 N is used to accelerate each of the following objects. 
Which of the objects will be travelling fastest after 5 seconds?

The green ball accelerates at a greater rate than the blue ball.

The balls will be moving at the same speed after 0.1 s.

The blue ball will be moving faster after 0.1 s.

The green ball will be moving faster after 0.1s

A blue and green snooker ball, of equal mass, have resultant forces acting them for 0.1 s, 20 N on the blue ball and 40 N on the green ball.
Which of the following statements are correct?

Place it on top of the trolley to keep the test fair.

It does not matter where the mass is placed.

Place it back on the mass holder to keep the test fair.

Remove an equal mass from the top of the trolley.

A pupil investigates how mass affects the acceleration of a trolley using hanging masses to produce a force. 
What should they do with a mass when they remove it from the mass holder?

Newton's Second Law

Lesson outcome