AQA Alevel Syllabus Year 1 (AS) 

3.1 Measurements and Errors 

3.1.1 Use of SI units and their prefixes 
3.1.2 Limitation of physical measurements 

Fundamental (base) units.
Use of mass, length, time, quantity of matter, temperature, electric current and their associated SI units.
SI units derived.
Knowledge and use of the SI prefixes, values and standard form.
The fundamental unit of light intensity, the candela, is excluded.
Students are not expected to recall definitions of the fundamental quantities. Dimensional analysis is not required.
Students should be able to use the prefixes: T, G, M, k, c, m, μ, n, p, f.
Students should be able to convert between different units of the same quantity, eg J and eV, J and kW h. 
(Units)

Random and systematic errors.
Precision, repeatability, reproducibility, resolution and accuracy.
Uncertainty: Absolute, fractional and percentage uncertainties represent uncertainty in the final answer for a quantity.
Combination of absolute and percentage uncertainties.
Represent uncertainty in a data point on a graph using error bars.
Determine the uncertainties in the gradient and intercept of a straightline graph.
Individual points on the graph may or may not have associated error bars.

(Uncertainty)
(Graphical Skills)

3.1.3 Estimation of physical quantities 
General Physics Skills (Expected as a matter of course) 

Orders of magnitude.
Estimation of approximate values of physical quantities 
Use of standard form.
Relationships between quantities.
Transposition of equations.
Presentation 
(Standard Form)
(Equations)
(Presentation) 

3.2 Particles and Radiation 

3.2.1 Particles 

3.2.1.1 Constituents of the atom 
3.2.1.2 Stable and unstable nuclei 

Simple model of the atom, including the proton, neutron and electron. Charge and mass of the proton, neutron and electron in SI units and relative units.
Nuclear physics section. Specific charge of the proton and the electron, and of nuclei and ions.
Proton number Z, nucleon number A, nuclide notation.
Students should be familiar with the isotope notation.
Meaning of isotopes and the use of isotopic data.

The strong nuclear force; its role in keeping the nucleus stable; shortrange attraction up to approximately 3 fm, veryshort range repulsion closer than approximately 0.5 fm.


The atomic mass unit (amu) is included in the Alevel. 

3.2.1.3 Particles, antiparticles and photons 
3.2.1.4 Particle interactions 

For every type of particle, there is a corresponding antiparticle.
Comparison of particle and antiparticle masses, charge and rest energy in MeV.
Students should know that the positron, antiproton, antineutron and antineutrino are the antiparticles of the electron, proton, neutron and neutrino respectively.

Four fundamental interactions: gravity, electromagnetic, weak nuclear, strong nuclear. (The strong nuclear force may be referred to as the strong interaction).
Simple
diagrams to represent the above reactions or 
(Feynman Diagrams)
(Exchange Particles) 

Photon model of electromagnetic radiation, the Planck constant.
E = h f = hc/l
Knowledge of annihilation and pair production and the energies involved.
The use of E = mc^{2} is not required in calculations.

Accelerators (Not on AQA Syllabus but useful for background) 

3.2.1.5 Classification of particles 
3.2.1.6 Quarks and antiquarks 

Hadrons are subject to the strong interaction.
The two classes of hadrons: • baryons (proton, neutron) and antibaryon (antiproton and antineutron) • mesons (pion, kaon).
Baryon number as a quantum number.
Conservation of baryon number.
The proton is the only stable baryon into which other baryons eventually decay. 
(Quarks) 
Properties of quarks and antiquarks: charge, baryon number and strangeness.
Combinations of quarks and antiquarks required for baryons (proton and neutron only), antibaryons (antiproton and antineutron only) and mesons (pion and kaon only).
Only knowledge of up (u), down (d) and strange (s) quarks and their antiquarks will be tested.
The decay of the neutron should be known. 

The pion as the exchange particle of the strong nuclear force.
The kaon as a particle that can decay into pions. 
3.2.1.7 Applications of conservation laws 

Leptons are subject to the weak interaction.
Leptons: electron, muon, neutrino (electron and muon types only) and their antiparticles.
Lepton number as a quantum number; conservation of lepton number for muon leptons and for electron leptons.
The muon as a particle that decays into an electron. 
Change of quark character in β− and in β+ decay.
Application of the conservation laws for charge, baryon number, lepton number and strangeness to particle interactions. The necessary data will be provided in questions for particles outside those specified.
Students should recognise that energy and momentum are conserved in interactions.


Strange particles as particles that are produced through the strong interaction and decay through the weak interaction (e.g. kaons).
Strangeness (symbol s) as a quantum number to reflect the fact that strange particles are always created in pairs.
Conservation of strangeness in strong interactions.
Strangeness can change by 0, +1 or 1 in weak interactions.
Appreciation that particle physics relies on the collaborative efforts of large teams of scientists and engineers to validate new knowledge. 


3.2.2 Electromagnetic radiation and quantum phenomena 

3.2.2.1 The photoelectric effect 
3.2.2.2 Collisions of electrons with atoms 

Threshold frequency; photon explanation of threshold frequency. 
Ionisation and excitation; understanding of ionisation and excitation in the fluorescent tube.



Work function f, stopping potential.
Photoelectric equation: h f = f + E _{k max}
E _{k max } is the maximum kinetic energy of the photoelectrons.
The experimental determination of stopping potential is not required.

The electron volt.
Students will be expected to be able to convert eV into J and vice versa.


3.2.2.3 Energy levels and photon emission 
3.2.2.4 Waveparticle duality 

Line spectra (eg of atomic hydrogen) as evidence for transitions between discrete energy levels in atoms.
In questions, energy levels may be quoted in J or eV. 
Students should know that electron diffraction suggests that particles possess wave properties and the photoelectric effect suggests that electromagnetic waves have a particulate nature.
de Broglie wavelength l = h/mv where mv is the momentum.


3.3 Waves 

3.3.1 Progressive and stationary waves 

3.3.1.1 Progressive waves 
3.3.1.2 Longitudinal and transverse waves 

Oscillation of the
particles of the medium;
c = f l
f = 1/T Phase difference may be measured as angles (radians and degrees) or as fractions of a cycle. 
Nature of longitudinal and transverse waves.


3.3.1.3 Principle of superposition of waves and formation of stationary waves 
3.3.2.1 Interference 

Stationary waves. Nodes and antinodes on strings.
for first harmonic. The formation of stationary waves by two waves of the same frequency travelling in opposite directions.
Stationary waves formed on a string and those produced with microwaves and sound waves should be considered.

(Superposition)
(Stationary Waves)
(Harmonics) 
Path difference. Coherence.
Young’s doubleslit experiment: the use of two coherent sources or
the use of a single source with double slits to produce an
interference pattern. Fringe spacing
Appreciation of how knowledge and understanding of nature of electromagnetic radiation has changed over time. 

3.3.2.2 Diffraction 
3.3.2.3 Refraction at a plane surface 

Appearance of the
diffraction pattern from a single slit using monochromatic and white
light. Qualitative treatment of the variation of the width of the central diffraction maximum with wavelength and slit width.
Applications of diffraction gratings. 
Refractive index of a substance,
Students should recall that the refractive index of air is approximately 1.
Snell’s law of refraction for a boundary:
Total internal reflection:
Simple treatment of fibre optics including the function of the cladding.
Optical fibres will be limited to step index only.
Material and modal dispersion.
Students are expected to understand the principles and consequences of pulse broadening and absorption.


3.4 Mechanics and Materials 

3.4.1 Force, energy and momentum 

3.4.1.1 Scalars and vectors 
3.4.1.2 Moments 

Nature of scalars and vectors
Problems may be solved either by the use of resolved forces or the use of a closed triangle.
Conditions for equilibrium for two or three coplanar forces acting at a point.
Appreciation of the
meaning of equilibrium in the context of an object at rest or moving 
(Vectors)
(Coplanar forces) 
Moment of a force about a point.
Principle of moments.

(Moments)
(Stability)
(Bridges) 
3.4.1.3 Motion along a straight line 
3.4.1.4 Projectile motion 

Displacement, speed, velocity, acceleration.
Calculations may
include average and instantaneous speeds and velocities. Representation by graphical methods of uniform and nonuniform acceleration.
Equations for
uniform acceleration:

Independent effect of motion in horizontal and vertical directions of a uniform gravitational field.
Problems will be solvable using the equations of uniform acceleration.
Qualitative understanding of the effect of air resistance on the trajectory of a projectile and on the factors that affect the maximum speed of a vehicle. 
(Terminal Speed)
(Friction)
(Projectile Motion) 

3.4.1.5 Newton’s laws of motion 
3.4.1.6 Momentum 

Knowledge and
application of the three laws of motion in appropriate situations. F = ma for situations where the mass is constant. 
momentum = mass ×
velocity Conservation of
linear momentum. Principle applied quantitatively to problems
in one dimension. Force as the rate of change of momentum,
Impulse = change in
momentum
where F is constant. Significance of the area under a force–time graph.

(Momentum and Impulse)
(Conservation) 

3.4.1.7 Work, energy and power 
3.4.1.8 Conservation of energy 

Energy transferred:
rate of doing work = rate of energy transfer,
Significance of the area under a force–displacement graph.

(Work)
(Efficiency) 
Principle of conservation of energy:
Quantitative and
qualitative application of energy 

3.4.2 Materials 

3.4.2.1 Bulk properties of solids 
3.4.2.2 The Young modulus 

Density:
Hooke’s law, elastic
limit:
k as stiffness and spring constant.
Appreciation of energy conservation issues in the context of ethical transport design. 
(Materials)
(Hooke's Law) 
Use of stress–strain
graphs to find the Young modulus. 

3.5 Electricity 

3.5.1 Current electricity 

3.5.1.1 Basics of electricity 
3.5.1.2 Current–voltage characteristics 

Electric current as the rate of flow of charge; potential difference as work done per unit charge.
Resistance defined as


For an ohmic
conductor, semiconductor diode, and

(Ohm's Law)
(Voltagecurrent characteristics)

3.5.1.3 Resistivity 
3.5.1.4 Circuits 

Resistivity:
Description of the qualitative effect of temperature on the resistance of metal conductors and thermistors.
Superconductivity as a property of certain materials which have zero resistivity at and below a critical temperature which depends on the material.

(Resistivity)
(Thermistors) 
Resistors:
E = IV t
The relationships
between currents, voltages and

(Circuits)
(Power)
(Cells) 
3.5.1.5 Potential divider 
3.5.1.6 Electromotive force and internal resistance 

The potential divider used to supply constant or variable potential difference from a power supply.
Examples should include the use of variable resistors, thermistors, and light dependent resistors (LDR) in the potential divider. 
Terminal pd; emf




