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Forces and motion

Forces, movement, shape and momentum

1.11-1.12 - Forces and their effectsForces are how bodies affect one another. A force can change how an object moves, or it can change the object's shape. In this lesson, you will learn to describe those effects and to identify common force types such as gravitational and electrostatic forces.
1.13-1.16 - Scalars, vectors and resultant forcesSome physical quantities are fully described by a number and a unit. Others also need a direction, and the direction changes the physics. In this lesson you will distinguish scalars from vectors, treat force as a vector, calculate resultant forces along one straight line, and use friction as a fo...
1.17-1.18 - Newton's second law and weightNewton's second law links the unbalanced force on an object to its mass and acceleration. Weight is a particular force: the pull of gravity on a mass. In this lesson you will learn what the symbols in the two equations mean, how to choose the right relationship, and how to avoid mixing up mass, w...
1.19-1.21 - Stopping distances and terminal velocityA moving vehicle does not stop at the instant the driver notices a hazard. It travels while the driver reacts, then travels farther while the brakes slow it down. Falling objects also change motion because their forces change as their speed changes, until some objects reach a steady speed called...
1.22-1.24 - Springs, Hooke's law and elastic behaviourStretching a spring, wire or rubber band is a simple way to see how a force can change the shape of an object. In this lesson you will learn how to measure extension, how to investigate the relationship between applied force and extension, and how to read the initial straight-line region of a for...
1.25P-1.28P - Momentum and safetyMomentum is a way to describe how much motion an object has. In a collision, momentum helps you predict what happens to objects and explain why safety features reduce injury. The important idea is not just "big things are dangerous"; it is that changing a large momentum quickly needs a large aver...
1.29P - Newton's third lawNewton's third law is about what happens when two objects interact. It does not say that forces disappear because they are equal and opposite. It says that a force is never alone: if one object exerts a force on another, the second object exerts an equal and opposite force on the first.
1.30P-1.33P - Moments, centre of gravity and equilibriumA force can do more than change the speed or shape of an object. If the force acts away from a pivot, it can have a turning effect called a moment. This lesson shows how to calculate moments, place weight through the centre of gravity, use the principle of moments, and explain the support forces...

Electricity

Energy and voltage in circuits

2.7-2.8 - Series and parallel circuitsSeries and parallel circuits are two different ways to connect components to a supply. The choice is not just a drawing style: it changes whether components depend on each other and how the current in the circuit responds when the supply or components change. In this lesson you will learn how to...
2.9-2.12 - Current-voltage graphs and electrical componentsCurrent-voltage graphs show how the current through a component changes when the voltage across it changes. Different components give different graph shapes, so the shape of the graph is evidence for how the component behaves in a circuit. In this lesson, the focus is qualitative: recognise the s...
2.13-2.16 - Voltage, current, resistance and chargeElectric circuits are easier to reason about when the four key quantities stay separate. Current tells you how quickly charge is flowing. Voltage, current and resistance are connected by one calculation relationship, and charge, current and time are connected by another. In metal wires, the movin...

Electric charge

Waves

Units and properties of waves

The electromagnetic spectrum

Light and sound

Energy resources and energy transfers

Units and energy transfers

Work and power

Energy resources and electricity generation

Solids, liquids and gases

Units, density and pressure

Change of state

Ideal gas molecules

Magnetism and electromagnetism

Units and magnetism

Electromagnetism

Electromagnetic induction

Radioactivity and particles

Units and radioactivity

Fission and fusion

Astrophysics

Units and motion in the universe

Stellar evolution

Cosmology