is a single force that represents the effect of all the forces on an object.

is the state of an object if there is no resultant force acting on it.

is a drawing on which forces are drawn end to end and to scale, which can be used to find a resultant force.

is one of two perpendicular forces that add up to a single force.

splits a force into two perpendicular forces that add up to that force.

Forces in two dimensions (including resolution of a force)

Combined science

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

Resultant forces and their effects

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

Newton's Second Law (including inertia)

Stopping

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

A helicopter is in the air in a state of equilibrium. Which of the following motions are possible?

A duck is swimming in a straight line across the surface of a lake at a steady speed. Which of the following free body diagrams correctly shows the forces acting on the duck?

Moving up at increasing speed, while also moving steadily to the right.

Moving to the left at decreasing speed, while also moving steadily upwards.

Moving to the left at decreasing speed, while also moving steadily downwards.

An aeroplane and its free body diagram are shown. Which of the following are possible descriptions of the aeroplane’s motion?

A spaceship in space uses two rockets to produce forces acting in two directions at the same time. Which of the following vector diagram shows how to find the resultant force?

The vector diagram shows the addition of three forces to find the resultant force. What is the magnitude of the resultant force?

The vector diagram shows a force on a grid of 1 cm squares. Which of the following is the correct description of the horizontal component of the force?

The diagram shows a force arrow drawn on a grid of 1 cm squares. What is the magnitude of the force?

There is a law of physics which states that an object will remain at rest, or in motion in a straight line at constant speed, unless a resultant force is acting on it. What is the name of this law?

What is the magnitude of the resultant force in this diagram?

The object is moving to the left at constant speed.

The object is moving to the right at constant speed.

The diagram shows an object with a single force acting on it. Which of the following are possible descriptions of the object’s motion?

A child throws a ball straight up. Which of the following is a correct free body diagram of the ball as it travels upwards?

Forces in two dimensions (including resolution of a force)

Lesson outcome