Numbers
OCR A-Level Physics A H556
Practical Skills in the Written Papers
The Practical Endorsement
Topic overviewAnalogue and digital measuring instrumentsImproving accuracy with repeat timing, fiducial markers and plumb linesTiming, calipers and micrometersConstructing and testing circuitsSignal generators and oscilloscopesGenerating and measuring wavesData loggers, modelling software and ionising radiation
Physical Quantities and Units
Making Measurements and Analysing Data
Nature of Quantities
Motion
Forces in Action
Work, Energy and Power
Materials
Newton’s Laws of Motion and Momentum
Charge and Current
Energy, Power and Resistance
Electrical Circuits
Waves
Topic overviewProgressive waves and their propertiesThe wave equationReflection, refraction and diffractionWave graphs and intensityThe electromagnetic spectrumPolarisationRefraction and refractive indexCritical angle and total internal reflectionThe principle of superpositionInterference, coherence and path differenceTwo-source interference, Young's double-slit experiment and the diffraction gratingForming stationary wavesStationary waves on strings and in air columnsMeasuring the speed of soundNode spacing, amplitude and phase in stationary wavesHarmonics and the fundamental mode
Quantum Physics
Thermal Physics
Topic overviewThermal equilibrium and absolute temperatureThe kinetic model of solids, liquids and gasesBrownian motion and internal energySpecific heat capacityMeasuring specific heat capacitySpecific latent heatMeasuring specific latent heatMoles, the Avogadro constant and kinetic theoryGas laws, the ideal gas equation and r.m.s. speedMaxwell-Boltzmann distribution, Boltzmann constant and internal energy
Oscillations
Gravitational Fields
Astrophysics and Cosmology
Topic overviewThe solar system and the birth of a starThe death of a low-mass starSupernovae, neutron stars and black holesThe Hertzsprung-Russell diagramEnergy levels and emission spectraAbsorption spectra and spectral linesPhoton energy and the diffraction gratingWien's law and Stefan's lawAstronomical distances, parallax and the cosmological principleDoppler shift and Hubble's lawThe expanding universe and the Big BangEvidence for the Big Bang and dark energy
Capacitors
Topic overviewCapacitance and charging a capacitorCapacitors in seriesCapacitors in parallel and combined circuitsEnergy stored by a capacitorCharging and discharging through a resistorInvestigating capacitor dischargeThe time constantIterative modelling, exponential decay and the constant-ratio property
Electric Fields
Electromagnetism
Nuclear and Particle Physics
Topic overviewAlpha-particle scattering and the nuclear modelProton number, nucleon number and isotopesThe strong nuclear force and nuclear radiusParticles, antiparticles and hadronsLeptons and the quark modelQuark composition and chargesBeta decay in the quark modelRadioactive decay and the three radiationsNuclear decay equationsActivity, decay constant and half-lifeExponential decay and radioactive datingMass-energy equivalenceAnnihilation, mass defect and binding energyBinding energy per nucleon and induced fissionThe fission reactor and nuclear wasteNuclear fusion and balancing nuclear equations
Materials
Force-extension graphs and work done
- 4 things to know
- Papers 1 and 3
Overview
Recall questions on plotting force-extension graphs, work done from the area under them, E = ½Fx, loading and unloading curves, rubber band behaviour and hysteresis, and a metal wire stretched beyond its elastic limit.
What you need to know
Answer each one before you reveal it.
Your recallNot started
Key term
What graph should be plotted after collecting force-extension data?
Key term
How can the work done in stretching a spring or wire be determined from a force-extension graph?
Key term
Describe the shape of a force-extension graph for a metal wire as it is stretched beyond its elastic limit.
Questions from this subtopic
Each one with the model answer underneath.
- 1
What graph should be plotted after collecting force-extension data?
Model answer
A force-extension graph
- 2
How can the work done in stretching a spring or wire be determined from a force-extension graph?
Model answer
The work done equals the area under the force-extension graph
- 3
State the formula for work done when stretching a material that obeys Hooke's law.
Model answer
E = ½Fx, where E is work done (or energy stored), F is force, and x is extension
- 4
Why is the formula for work done E = ½Fx rather than E = Fx for a spring obeying Hooke's law?
Model answer
Because the force increases linearly from zero to F as the spring extends, so the average force is ½F
- 5
What does the area between the loading and unloading curves on a force-extension graph represent?
Model answer
Energy dissipated as heat
- 6
Describe two characteristic features of the force-extension behaviour of rubber bands.
Model answer
Rubber bands show non-linear force-extension behaviour and exhibit hysteresis when loading and unloading
Other ways to work this
The same content, four other ways.
What is inside Levo
Six ways to work the same material.
Every question in Materials, on a schedule.
Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.
Or £46 a year, about £3.83 a month. Cancel anytime.