Pearson Edexcel International GCSE in Physics Specification

Forces and Motion

Units

Kilogram (kg)
Metre (m)
Metre/second (m/s)
Metre/second squared (m/s²)
Newton (N)
Second (s)
Newton/kilogram (N/kg)
Newton metre (Nm)
Kilogram metre/second (kg m/s)

Movement and Position

Plotting and explaining distance-time graphs.
Relationship between average speed, distance moved, and time taken: $average \, speed = \frac{distance \, moved}{time \, taken}$
Practical investigation of motion of everyday objects.
Relationship between acceleration, change in velocity, and time taken: $acceleration = \frac{change \, in \, velocity}{time \, taken}$ , which can be written as $a = \frac{v - u}{t}$
Plotting and explaining velocity-time graphs.
Determining acceleration from the gradient of a velocity-time graph.
Determining the distance travelled from the area between a velocity-time graph and the time axis.
Relationship between final speed, initial speed, acceleration, and distance moved: $(final \, speed)^2 = (initial \, speed)^2 + (2 \times acceleration \times distance \, moved)$ , which can be written as $v^2 = u^2 + (2 \times a \times s)$

Forces, Movement, Shape, and Momentum

Effects of forces between bodies: changes in speed, shape, or direction.
Different types of forces: gravitational, electrostatic, etc.
Difference between vector and scalar quantities.
Force is a vector quantity.
Calculating the resultant force of forces that act along a line.
Friction is a force that opposes motion.
Relationship between unbalanced force, mass, and acceleration: $force = mass \times acceleration$ , which can be written as $F = m \times a$
Relationship between weight, mass, and gravitational field strength: $weight = mass \times gravitational \, field \, strength$ , which can be written as $W = m \times g$
Stopping distance of a vehicle: sum of thinking distance and braking distance.
Factors affecting vehicle stopping distance: speed, mass, road condition, and reaction time.
Forces acting on falling objects and terminal velocity.
Practical investigation: how extension varies with applied force for helical springs, metal wires, and rubber bands.
Initial linear region of a force-extension graph is associated with Hooke’s law.
Elastic behavior: ability of a material to recover its original shape after the forces causing deformation have been removed.
Relationship between momentum, mass, and velocity: $momentum = mass \times velocity$ , which can be written as $p = m \times v$
Using the idea of momentum to explain safety features.
Using the conservation of momentum to calculate mass, velocity, or momentum of objects.
Relationship between force, change in momentum, and time taken: $force = \frac{change \, in \, momentum}{time \, taken}$ , which can be written as $F = \frac{(m \times v) - (m \times u)}{t}$
Understanding of Newton’s third law.
Relationship between the moment of a force and its perpendicular distance from the pivot: $moment = force \times perpendicular \, distance \, from \, the \, pivot$
The weight of a body acts through its center of gravity.
Using the principle of moments for a simple system of parallel forces acting in one plane.
Understanding how the upward forces on a light beam, supported at its ends, vary with the position of a heavy object placed on the beam.

Electricity

Units

Ampere (A)
Coulomb (C)
Joule (J)
Ohm (Ω)
Second (s)
Volt (V)
Watt (W)

Mains Electricity

How insulation, double insulation, earthing, fuses, and circuit breakers protect devices or users in domestic appliances.
Why a current in a resistor results in electrical transfer of energy and an increase in temperature and its use in domestic contexts.
Relationship between power, current, and voltage: $power = current \times voltage$ , which can be written as $P = I \times V$ and apply the relationship to the selection of appropriate fuses.
Relationship between energy transferred, current, voltage, and time: $energy \, transferred = current \times voltage \times time$ , which can be written as $E = I \times V \times t$
Difference between mains electricity being alternating current (a.c.) and direct current (d.c.) being supplied by a cell or battery.

Energy and Voltage in Circuits

Why a series or parallel circuit is more appropriate for particular applications, including domestic lighting.
How the current in a series circuit depends on the applied voltage and the number and nature of other components.
How current varies with voltage in wires, resistors, metal filament lamps, and diodes, and how to investigate this experimentally.
Qualitative effect of changing resistance on the current in a circuit.
Qualitative variation of resistance of light-dependent resistors (LDRs) with illumination and thermistors with temperature.
Lamps and LEDs can be used to indicate the presence of a current in a circuit.
Relationship between voltage, current, and resistance: $voltage = current \times resistance$ , which can be written as $V = I \times R$
Current is the rate of flow of charge.
Relationship between charge, current, and time: $charge = current \times time$ , which can be written as $Q = I \times t$
Electric current in solid metallic conductors is a flow of negatively charged electrons.
Why current is conserved at a junction in a circuit.
The voltage across two components connected in parallel is the same.
Calculating the currents, voltages, and resistances of two resistive components connected in a series circuit.
Voltage is the energy transferred per unit charge passed.
The volt is a joule per coulomb.
Relationship between energy transferred, charge, and voltage: $energy \, transferred = charge \times voltage$ , which can be written as $E = Q \times V$

Electric Charge

Common materials that are electrical conductors or insulators, including metals and plastics.
Practical investigation: how insulating materials can be charged by friction.
How positive and negative electrostatic charges are produced on materials by the loss and gain of electrons.
Forces of attraction between unlike charges and forces of repulsion between like charges.
Electrostatic phenomena in terms of the movement of electrons.
Potential dangers of electrostatic charges, e.g. when fuelling aircraft and tankers.
Some uses of electrostatic charges, e.g. in photocopiers and inkjet printers.

Waves

Units

Degree (°)
Hertz (Hz)
Metre (m)
Metre/second (m/s)
Second (s)

Properties of Waves

Difference between longitudinal and transverse waves.
Definitions of amplitude, wavefront, frequency, wavelength, and period of a wave.
Waves transfer energy and information without transferring matter.
Relationship between the speed, frequency, and wavelength of a wave: $wave \, speed = frequency \times wavelength$ , which can be written as $v = f \times λ$
Relationship between frequency and time period: $frequency = \frac{1}{time \, period}$ , which can be written as $f = \frac{1}{T}$
Using the above relationships in different contexts, including sound waves and electromagnetic waves.
Why there is a change in the observed frequency and wavelength of a wave when its source is moving relative to an observer, known as the Doppler effect.
All waves can be reflected and refracted.

The Electromagnetic Spectrum

Light is part of a continuous electromagnetic spectrum that includes radio, microwave, infrared, visible, ultraviolet, x-ray, and gamma ray radiations, and that all these waves travel at the same speed in free space.
Order of the electromagnetic spectrum in terms of decreasing wavelength and increasing frequency, including the colors of the visible spectrum.
Some of the uses of electromagnetic radiations, including:
- Radio waves: broadcasting and communications
- Microwaves: cooking and satellite transmissions
- Infrared: heaters and night vision equipment
- Visible light: optical fibers and photography
- Ultraviolet: fluorescent lamps
- X-rays: observing the internal structure of objects and materials, including for medical applications
- Gamma rays: sterilizing food and medical equipment
Detrimental effects of excessive exposure of the human body to electromagnetic waves, including:
- Microwaves: internal heating of body tissue
- Infrared: skin burns
- Ultraviolet: damage to surface cells and blindness
- Gamma rays: cancer, mutation and describe simple protective measures against the risks

Light and Sound

Light waves are transverse waves that can be reflected and refracted.
The law of reflection (the angle of incidence equals the angle of reflection).
Drawing ray diagrams to illustrate reflection and refraction.
Practical investigation: the refraction of light, using rectangular blocks, semi-circular blocks, and triangular prisms.
Relationship between refractive index, angle of incidence, and angle of refraction: $n = \frac{sin \, i}{sin \, r}$
Practical investigation: the refractive index of glass, using a glass block.
The role of total internal reflection in transmitting information along optical fibers and in prisms.
Meaning of critical angle.
Relationship between critical angle and refractive index: $n = \frac{1}{sin \, c}$
Sound waves are longitudinal waves that can be reflected and refracted.
The frequency range for human hearing is 20–20 000 Hz.
Practical investigation: the speed of sound in air.
How an oscilloscope and microphone can be used to display a sound wave.
Practical investigation: the frequency of a sound wave using an oscilloscope.
How the pitch of a sound relates to the frequency of vibration of the source.
How the loudness of a sound relates to the amplitude of vibration of the source.

Energy Resources and Energy Transfers

Units

Kilogram (kg)
Joule (J)
Metre (m)
Metre/second (m/s)
Metre/second squared (m/s²)
Newton (N)
Second (s)
Watt (W)

Energy Transfers

Energy transfers involving energy stores:
- Energy stores: chemical, kinetic, gravitational, elastic, thermal, magnetic, electrostatic, nuclear
- Energy transfers: mechanically, electrically, by heating, by radiation (light and sound)
Using the principle of conservation of energy.
Relationship between efficiency, useful energy output, and total energy output: $efficiency = \frac{useful \, energy \, output}{total \, energy \, output} \times 100\%$
Describing a variety of everyday and scientific devices and situations, explaining the transfer of the input energy in terms of the above relationship, including their representation by Sankey diagrams.
How thermal energy transfer may take place by conduction, convection, and radiation.
The role of convection in everyday phenomena.
How emission and absorption of radiation are related to surface and temperature.
Practical investigation: thermal energy transfer by conduction, convection, and radiation.
Ways of reducing unwanted energy transfer, such as insulation.

Work and Power

Relationship between work done, force and distance moved in the direction of the force: $work \, done = force \times distance \, moved$ , which can be written as $W = F \times d$
Work done is equal to energy transferred.
Relationship between gravitational potential energy, mass, gravitational field strength, and height: $gravitational \, potential \, energy = mass \times gravitational \, field \, strength \times height$ , which can be written as $GPE = m \times g \times h$
Relationship: $kinetic \, energy = \frac{1}{2} \times mass \times speed^2$ , which can be written as $KE = \frac{1}{2} \times m \times v^2$
How conservation of energy produces a link between gravitational potential energy, kinetic energy, and work.
Power as the rate of transfer of energy or the rate of doing work.
Relationship between power, work done (energy transferred) and time taken: $power = \frac{work \, done}{time \, taken}$ , which can be written as $P = \frac{W}{t}$

Energy Resources and Electricity Generation

Energy transfers involved in generating electricity using:
- Wind
- Water
- Geothermal resources
- Solar heating systems
- Solar cells
- Fossil fuels
- Nuclear power
Advantages and disadvantages of methods of large-scale electricity production from various renewable and non-renewable resources.

Solids, Liquids and Gases

Units

Degree Celsius (°C)
Kelvin (K)
Joule (J)
Kilogram (kg)
Kilogram/metre cubed (kg/m³)
Metre (m)
Metre squared (m²)
Metre cubed (m³)
Metre/second (m/s)
Metre/second squared (m/s²)
Newton (N)
Pascal (Pa)
Joules/kilogram degree Celsius (J/kg °C)

Density and Pressure

Relationship between density, mass and volume: $density = \frac{mass}{volume}$ , which can be written as $ρ = \frac{m}{V}$
Practical investigation: density using direct measurements of mass and volume.
Relationship between pressure, force and area: $pressure = \frac{force}{area}$ , which can be written as $p = \frac{F}{A}$
How the pressure at a point in a gas or liquid at rest acts equally in all directions.
Relationship for pressure difference: $pressure \, difference = height \times density \times gravitational \, field \, strength$ , which can be written as $p = h \times ρ \times g$

Change of State

Why heating a system will change the energy stored within the system and raise its temperature or produce changes of state.
Changes that occur when a solid melts to form a liquid, and when a liquid evaporates or boils to form a gas.
Arrangement and motion of particles in solids, liquids and gases.
Practical: obtain a temperature–time graph to show the constant temperature during a change of state
Specific heat capacity is the energy required to change the temperature of an object by one degree Celsius per kilogram of mass (J/kg °C).
Equation: $change \, in \, thermal \, energy = mass \times specific \, heat \, capacity \times change \, in \, temperature$ , which can be written as $ΔQ = m \times c \times ΔT$
Practical investigation: the specific heat capacity of materials including water and some solids

Ideal Gas Molecules

How molecules in a gas have random motion and that they exert a force, and hence a pressure, on the walls of a container.
Why there is an absolute zero of temperature, which is –273 °C.
Description of the Kelvin scale of temperature and be able to convert between the Kelvin and Celsius scales.
Why an increase in temperature results in an increase in the average speed of gas molecules.
Kelvin temperature of a gas is proportional to the average kinetic energy of its molecules.
For a fixed amount of gas, the qualitative relationship between:
- pressure and volume at constant temperature
- pressure and Kelvin temperature at constant volume
Relationship between the pressure and Kelvin temperature of a fixed mass of gas at constant volume: $\frac{p1}{T1} = \frac{p2}{T2}$
Relationship between the pressure and volume of a fixed mass of gas at constant temperature: $p1V1 = p2V2$

Magnetism and Electromagnetism

Units

Ampere (A)
Volt (V)
Watt (W)

Magnetism

Magnets repel and attract other magnets and attract magnetic substances.
Properties of magnetically hard and soft materials.
Understanding the term 'magnetic field line'.
Magnetism is induced in some materials when they are placed in a magnetic field.
Practical investigation: the magnetic field pattern for a permanent bar magnet and between two bar magnets.
How to use two permanent magnets to produce a uniform magnetic field pattern.

Electromagnetism

An electric current in a conductor produces a magnetic field around it.
Construction of electromagnets.
Drawing magnetic field patterns for a straight wire, a flat circular coil and a solenoid when each is carrying a current.
There is a force on a charged particle when it moves in a magnetic field as long as its motion is not parallel to the field.
Why a force is exerted on a current-carrying wire in a magnetic field and how this effect is applied in simple d.c. electric motors and loudspeakers.
Using the left-hand rule to predict the direction of the resulting force when a wire carries a current perpendicular to a magnetic field.
How the force on a current-carrying conductor in a magnetic field changes with the magnitude and direction of the field and current.

Electromagnetic Induction

A voltage is induced in a conductor or a coil when it moves through a magnetic field or when a magnetic field changes through it and describe the factors that affect the size of the induced voltage.
Generation of electricity by the rotation of a magnet within a coil of wire and of a coil of wire within a magnetic field, and describe the factors that affect the size of the induced voltage.
Description of the structure of a transformer and understand that a transformer changes the size of an alternating voltage by having different numbers of turns on the input and output sides.
Explanation of the use of step-up and step-down transformers in the large-scale generation and transmission of electrical energy.
Relationship between input (primary) and output (secondary) voltages and the turns ratio for a transformer: $\frac{input \, (primary) \, voltage}{output \, (secondary) \, voltage} = \frac{primary \, turns}{secondary \, turns}$
Relationship: input power = output power for 100% efficiency: $Vp \times Ip = Vs \times Is$

Radioactivity and Particles

Units

Becquerel (Bq)
Centimetre (cm)
Hour (h)
Minute (min)
Second (s)

Radioactivity

Description of the structure of an atom in terms of protons, neutrons and electrons and use symbols such as $^{14}_{6}C$ to describe particular nuclei.
Terms: atomic (proton) number, mass (nucleon) number and isotope.
Alpha (α) particles, beta (β−) particles, and gamma (γ) rays are ionizing radiations emitted from unstable nuclei in a random process.
Nature of alpha (α) particles, beta (β−) particles and gamma (γ) rays, and recall that they may be distinguished in terms of penetrating power and ability to ionise.
Practical investigation: the penetration powers of different types of radiation using either radioactive sources or simulations.
Effects on the atomic and mass numbers of a nucleus of the emission of each of the four main types of radiation (alpha, beta, gamma and neutron radiation).
How to balance nuclear equations in terms of mass and charge.
Photographic film or a Geiger−Müller detector can detect ionizing radiations.
Sources of background (ionizing) radiation from Earth and space.
The activity of a radioactive source decreases over a period of time and is measured in becquerels.
Definition of the term 'half-life' and understand that it is different for different radioactive isotopes.
Using the concept of the half-life to carry out simple calculations on activity, including graphical methods.
Uses of radioactivity in industry and medicine.
Difference between contamination and irradiation.
Dangers of ionizing radiations, including:
- Radiation can cause mutations in living organisms
- Radiation can damage cells and tissue
- Problems arising from the disposal of radioactive waste and how the associated risks can be reduced

Fission and Fusion

Nuclear reactions, including fission, fusion and radioactive decay, can be a source of energy.
How a nucleus of U-235 can be split (the process of fission) by collision with a neutron and that this process releases energy as kinetic energy of the fission products.
The fission of U-235 produces two radioactive daughter nuclei and a small number of neutrons.
How a chain reaction can be set up if the neutrons produced by one fission strike other U-235 nuclei.
Role played by the control rods and moderator in the fission process.
The role of shielding around a nuclear reactor.
Difference between nuclear fusion and nuclear fission.
Nuclear fusion as the creation of larger nuclei resulting in a loss of mass from smaller nuclei, accompanied by a release of energy.
Fusion is the energy source for stars.
Why nuclear fusion does not happen at low temperatures and pressures, due to electrostatic repulsion of protons

Astrophysics

Units

Kilogram (kg)
Metre (m)
Metre/second (m/s)
Metre/second squared (m/s²)
Newton (N)
Second (s)
Newton/kilogram (N/kg)

Motion in the Universe

The universe is a large collection of billions of galaxies.
A galaxy is a large collection of billions of stars.
Our solar system is in the Milky Way galaxy.
Why gravitational field strength, g, varies and know that it is different on other planets and the Moon from that on the Earth.
Gravitational force:
- Causes moons to orbit planets
- Causes the planets to orbit the Sun
- Causes artificial satellites to orbit the Earth
- Causes comets to orbit the Sun
Differences in the orbits of comets, moons and planets.
Relationship between orbital speed, orbital radius and time period: $orbital \, speed = \frac{2 \times π \times orbital \, radius}{time \, period}$ , which can be written as $v = \frac{2 \times π \times r}{T}$

Stellar Evolution

How stars can be classified according to their color.
A star’s color is related to its surface temperature.
Evolution of stars of similar mass to the Sun through the following stages:
- Nebula
- Star (main sequence)
- Red giant
- White dwarf
Evolution of stars with a mass larger than the Sun.
How the brightness of a star at a standard distance can be represented using absolute magnitude.
Drawing the main components of the Hertzsprung–Russell diagram (HR diagram)

Cosmology

Description of the past evolution of the universe and the main arguments in favor of the Big Bang theory.
Description of evidence that supports the Big Bang theory
- Red-shift
- Cosmic microwave background (CMB) radiation
Description that if a wave source is moving relative to an observer, there will be a change in the observed frequency and wavelength.
Equation relating to change in wavelength, reference wavelength, velocity of a galaxy and the speed of light: $\frac{velocity \, of \, a \, galaxy}{speed \, of \, light} = \frac{change \, in \, wavelength}{reference \, wavelength}$ , which can be written as $\frac{v}{c} = \frac{Δλ}{λ_0}$
Description of the red-shift in light received from galaxies at different distances away from the Earth.
Explanation of why the red-shift of galaxies provides evidence for the expansion of the universe.