Specification points
WJEC AS Physics 2420QS
151 points in 2 topics, with WJEC's codes and titles.
Codes and titles are read by a script from WJEC's published specification and have not been checked by a person. What each point covers is in the specification itself: WJEC’s specification.
1 AS Unit 1: Motion, Energy and Matter
- 1.1 Basic Physics
- 1.1(a) The 6 essential base SI units (kg, m, s, A, mol, K)
- 1.1(b) SI base units and prefixes
- 1.1(c) Checking equations for homogeneity using units
- 1.1(d) Scalar and vector quantities
- 1.1(e) Adding and subtracting coplanar vectors
- 1.1(f) Resolving vectors into components
- 1.1(g) Density
- 1.1(h) Turning effect of a force
- 1.1(i) The use of the principle of moments
- 1.1(j) Centre of gravity and stability
- 1.1(k) Equilibrium: resultant force and moment
- 1.2 Kinematics
- 1.2(a) Displacement, speed, velocity and acceleration
- 1.2(b) The representation of displacement, speed, velocity and acceleration by graphical methods
- 1.2(c) Displacement-time and velocity-time graphs
- 1.2(d) Equations of uniformly accelerated motion
- 1.2(e) Falling bodies and terminal velocity
- 1.2(f) Independence of vertical and horizontal motion
- 1.2(g) Projectile motion
- 1.3 Dynamics
- 1.3(a) The concept of force and Newton's 3rd law of motion
- 1.3(b) Free body diagrams
- 1.3(c) Newton's second law, F = ma
- 1.3(d) Linear momentum
- 1.3(e) Force as rate of change of momentum
- 1.3(f) Conservation of momentum; elastic and inelastic collisions
- 1.4 Energy Concepts
- 1.4(a) Work done by a force
- 1.4(b) Work done when force is not along the motion
- 1.4(c) Conservation of energy
- 1.4(d) The work–energy relationship
- 1.4(e) Power being the rate of energy transfer
- 1.4(f) Dissipative forces and efficiency
- 1.4(g) Efficiency as a percentage
- 1.5 Solids Under Stress
- 1.5(a) Hooke's law and the spring constant
- 1.5(b) Tensile stress, strain and the Young modulus
- 1.5(c) Work done in deforming a solid
- 1.5(d) Crystalline, amorphous and polymeric solids
- 1.5(e) Force-extension graphs for ductile metals
- 1.5(f) Force-extension graphs for brittle materials
- 1.5(g) Force–extension and stress–strain graphs for rubber
- 1.6 Using Radiation to Investigate Stars
- 1.6(a) Stellar spectra
- 1.6(b) Black bodies
- 1.6(c) Black body spectrum and peak wavelength
- 1.6(d) Wien's law, Stefan's law and properties of stars
- 1.6(e) Multiwavelength astronomy
- 1.7 Particles and Nuclear Structure
- 1.7(a) Quarks and leptons
- 1.7(b) Antiparticles
- 1.7(c) Symbols for a positron and for antiparticles of quarks and hadrons
- 1.7(d) Hadrons, baryons and mesons
- 1.7(e) The quark compositions of the neutron and proton
- 1.7(f) Quark make-up of baryons and pions
- 1.7(g) The four fundamental forces
- 1.7(h) Conservation laws in particle reactions
- 1.7(i) Weak interactions: neutrinos and quark flavour changes
2 AS Unit 2: Electricity and Light
- 2.1 Conduction of Electricity
- 2.1(a) Charge and the coulomb
- 2.1(b) Conductors and the flow of charge
- 2.1(c) Electric current being the rate of flow of charge
- 2.1(d) Current equation I = ΔQ/Δt
- 2.1(e) The ampere as one coulomb per second
- 2.1(f) The mechanism of conduction in metals as the drift of free electrons
- 2.1(g) Current and drift velocity, I = nAve
- 2.2 Resistance
- 2.2(a) The definition of potential difference
- 2.2(b) Potential difference and the volt
- 2.2(c) I–V graphs for a filament lamp and a metal wire
- 2.2(d) Ohm's law, the equation V = IR and the definition of resistance
- 2.2(e) The ohm
- 2.2(f) Equations for electrical power
- 2.2(g) Resistance from electron–ion collisions
- 2.2(h) The resistivity equation
- 2.2(i) Resistance of metals and temperature
- 2.2(j) Collisions and heating in metals
- 2.2(k) Superconductivity and transition temperature
- 2.2(l) Superconducting transition temperatures of metals
- 2.2(m) High-temperature superconductors
- 2.2(n) Uses of superconductors
- 2.3 D.C. Circuits
- 2.3(a) Currents in parallel circuits
- 2.3(b) Potential differences in series circuits
- 2.3(c) Potential differences across parallel components
- 2.3(d) Combined resistance in series and parallel
- 2.3(e) Potential dividers
- 2.3(f) Electromotive force of a source
- 2.3(g) The unit of emf
- 2.3(h) Internal resistance
- 2.3(i) Current and potential difference with cells in series
- 2.4 The Nature of Waves
- 2.4(a) Progressive waves and energy transfer
- 2.4(b) The difference between transverse and longitudinal waves
- 2.4(c) The term polarisation
- 2.4(d) The terms in phase and in antiphase
- 2.4(e) The terms displacement, amplitude, wavelength, frequency, period and velocity of a wave
- 2.4(f) Displacement graphs for transverse waves
- 2.4(g) Wave equation c = fλ
- 2.4(h) Wavefronts, phase and rays
- 2.5 Wave Properties
- 2.5(a) Diffraction occuring when waves encounter slits or obstacles
- 2.5(b) Little diffraction at large gaps
- 2.5(c) Diffraction and slit width
- 2.5(d) Two-source interference
- 2.5(e) The historical importance of Young’s experiment
- 2.5(f) The principle of superposition, giving appropriate sketch graphs
- 2.5(g) Path difference and interference
- 2.5(h) Young's double slit equation
- 2.5(i) The diffraction grating equation
- 2.5(j) Diffraction gratings compared with Young's slits
- 2.5(k) Coherent sources
- 2.5(l) Examples of coherent and incoherent sources
- 2.5(m) Conditions for observing two-source interference
- 2.5(n) The differences between stationary and progressive waves
- 2.5(o) Stationary waves as superposition
- 2.6 Refraction of Light
- 2.6(a) Refractive index
- 2.6(b) Snell's law
- 2.6(c) Snell's law and the wave model of light
- 2.6(d) The conditions for total internal reflection
- 2.6(e) Critical angle
- 2.6(f) Total internal reflection in multimode fibres
- 2.6(g) Multimode dispersion in optical fibres
- 2.6(h) Monomode optical fibres
- 2.7 Photons
- 2.7(a) Photons as packets of energy
- 2.7(b) Demonstrating the photoelectric effect
- 2.7(c) Measuring maximum kinetic energy with a vacuum photocell
- 2.7(d) Graph of maximum kinetic energy against frequency
- 2.7(e) Einstein's photoelectric equation
- 2.7(f) The electromagnetic spectrum
- 2.7(g) Typical photon energies for these radiations
- 2.7(h) Producing line emission and absorption spectra
- 2.7(i) The appearance of such spectra as seen in a diffraction grating
- 2.7(j) Energy level diagrams and line spectra
- 2.7(k) Ionisation energies from energy level diagrams
- 2.7(l) Electron diffraction and wave-particle duality
- 2.7(m) The de Broglie relationship
- 2.7(n) The calculation of radiation pressure on a surface absorbing or reflecting photons
- 2.8 Lasers
- 2.8(a) Stimulated emission
- 2.8(b) Population inversion in lasers
- 2.8(c) Population inversion and two-level systems
- 2.8(d) Population inversion in three- and four-level systems
- 2.8(e) The process of pumping and its purpose
- 2.8(f) Structure of a laser
- 2.8(g) Semiconductor lasers: advantages and uses