The extension of a spring is the change in length.

Masses will have a gravitational force that pulls them downwards.

Hanging masses (weights) can be used to put a known force onto a spring.

A mass hanger can be attached to a spring; adding masses to it causes the spring to stretch in a controlled way.

Stretching springs

Science

Gravitational force and weight

Hooke's law

Stretching rubber

The force of a floor

Levers

Turning forces

Floating, mass and shape

Pressure

Pressure at different depths and heights

In the Particle explanations of density and pressure unit, pupils will build on this knowledge to learn how the arrangement and movement of particles in solids, liquids and gases explain density, pressure, floating and convection.

In the Forces unit, pupils learnt how to accurately describe and explain the actions of forces in a range of situations.

This unit explores forces, deformation, Hooke’s Law, moments, and work done. It covers pressure in liquids, atmospheric pressure, upthrust, and equilibrium, as well as simple machines and force-extension relationships, highlighting how forces affect motion, friction, and object deformation.

Hidden forces

Physical activity and equipment requiring safe use

The change in length of an object when a force acts on it.

A force that pulls objects downwards due to their mass.

Metal discs used to produce forces on a spring.

This is used to attach masses to the end of a spring.

Match the key words and phrases to their explanation.

A spring is 10 cm long when there is no force on it. What is its length when it has been extended by 5 cm?

Only use small forces to stretch the spring.

Line up the ruler's zero with the bottom of the unloaded spring.

Line up the ruler's zero with the top of the unloaded spring.

Line up the ruler's zero with the top of the fully loaded spring.

Which of these allows the readings from a ruler to be used to measure the extension of a spring directly?

The loading and unloading measurements match closely.

The table shows the results of an experiment to find out how a spring extends. How do the results show that the measurements have been made accurately?

The spring gets longer each time 1 N is added.

All springs stretch the same way each time 1 N is added.

All springs stretch the same amount each time 1 N is added.

The table shows the results of an experiment to find out how a spring extends. Which statements can be made from the results?

The table shows how a spring extends. The spring was originally 10 cm long. Use the results to predict the length of the spring when a force of 10 N is acting on the spring.

Somebody slides down a slide. What force is causing them to speed up as they slide?

Somebody slides down a slide. What two forces are opposing the motion as they slide?

Which of the following can a force do to an object?

Some masses are placed on a balance. Which force acts downwards on the masses?

The spring stretches more when there is a larger force on it.

The spring stretches less when there is a larger force on it.

The spring makes the meter strong enough to hold things.

The image shows a newton meter which has a spring inside it. Why is a spring used in the newton meter?

There is an upwards magnetic force acting on the paperclip.

The downwards gravitational force is equal to the upwards magnetic force.

There is downwards force on the paperclip due to tension in the thread.

The tension in the thread is equal to the upwards magnetic force.

The upwards and downwards forces are equal so there is no resultant force.

The picture shows a steel paperclip on some thread being attracted by a magnet. The paperclip is stationary. Which statements must be true?

Stretching springs

Lesson outcome

Content guidance