Materials Science within AS and A-level Physics

Elizabeth Swinbank

Director, Salters Horners Advanced PhysicsUniversity of York

All AS and A-level specifications (syllabuses) are changing for first teaching in September 2008

All the new physics specs have

4 content assessment units (2 AS, 2 A2)

2 coursework assessment units (1 AS, 1 A2)

a requirement to address ‘how science works’

Most have

little or no optional content

See IOP summary for details of assessment structures

Changes to AS/A-level physics

Materials Science content is predominantly in AS

AS core content includesresistivityrefractive index

At AS, nearly all specs require mechanical propertiesHooke’s lawYoung modulusstress-strain graphselastic and plastic behaviourmeaning of terms brittle, hard etc

A2 core content includesspecific heat capacity

There is essentially no other Materials Science content in any A2 physics specification

See Appendix for details of individual spec requirements

Examples of content requirements

Draw force-extension, force-compression, and tensile/compressive stress-strain graphs. Identify the limit of proportionality, elastic limit and yield point (Edexcel)

One method of measuring Young modulus and fracture stress (OCR B)

Describe how to determine the resistivity of a metalwire experimentally (WJEC)

Refractive index of a substance is given by n = c/v (AQA B)

How Science Works

Nature and limitations of scientific knowledge (hypothesis and prediction, data and explanation, modelling, the scientific community)

Scientific enquiry (experimental skills, data handling, mathematical skills)

Communication (scientific language, presentation of data)

Applications and implications (decision making, risk, ethics)

Coursework

All specifications require practical coursework at AS and A2.

Students undertake a practical task (or tasks) that are either set by the awarding body or devised by their teachers.

Typically, the exercise takes about 1 hour to complete.

The exact requirements vary between specifications.

Examples of AS practical coursework requirements

Use and be familiar with standard laboratory equipment (eg electric meters… vernier callipers … newtonmeters... electronic balance …) (AQA)

Take measurements and record data showing awarenessof the limits of accuracy … (WJEC)

Analyse and interpret data to provide evidence, recognising correlations and causal relationships(OCR A)

Visit or case study

The Edexcel specification for AS requires a report of a visit or case study.

The practical task should be linked to the visit/case study.

Example

Visit a biscuit factory: observe mechanical testing of products for quality control

Practical: measure elastic modulus of ice-cream wafer

Materials activities from Salters Horners Advanced Physics (Edexcel)

Context-led course

Food industry: product development and quality control

Spare part surgery: designer materials

Eat sweets to establish the meaning of technical terms brittle, hard, etc

  

Plot force-extension graphs for strawberry laces

Measure Brinnell hardness of mints

Measure breaking stress of model bone

Determine Young modulus of UHMWPE for use in hip replacements

A blueprint for the development of Materials Science resources

Focus on mechanical properties for AS level

Include electrical, thermal and optical properties

Address ‘how science works’

Develop experimental skills

Put activities in authentic (and novel) contexts

Appendix

Materials Science elements of the new AS and A-level physics specifications

AQA AAQA B (Physics in Context)Edexcel (includes SHAP)OCR AOCR B (Advancing Physics)WJEC

AQA AUnit 1 Particles, Quantum Phenomena and Electricity

resistivitysuperconductivity

Unit 2 Mechanics, Materials and Waves density

Hooke’s lawtensile stress and strainenergy storedbreaking stressplastic behaviourfracture and brittlenessstress-strain curvesYoung modulus

AQA A

Unit 5 Nuclear Physics, Thermal Physics and an Optional Topic

specific heat capacity

AQA B (Physics in context)

Unit 1 Harmony and Structure in the Universerefractive index

Unit 2 Physics Keeps us Goingelastic potential energystiffness (of a sample)thermal conductivityU valuesresistivitysuperconductivity

Unit 5 Energy Under the Microscopespecific heat capacity

Edexcel (SHAP)

Unit 1 Physics on the godensitylaminar and turbulent flowviscosity and Stokes’s lawHooke’s lawcompressive and tensile stress and strainstress-strain graphsYoung moduluselastic and plastic behaviourbreaking stressenergy storedmeaning of brittle, hard, ductile, malleable, stiff, tough

Edexcel (SHAP)

Unit 2 Physics at work

resistivitytemperature and resistancerefractive index

Unit 5 Physics from creation to collapse

specific heat capacity

OCR AUnit 1 Mechanics

tensile and compressive deformationHooke’s lawstored energystress and strainYoung modulusbreaking stresselastic and plastic deformationstress-strain graphs

Unit 2 Electrons, Waves and Photonsresistivitytemperature and resistancesuperconductivity

OCR B (Advancing Physics)

Unit 1 Physics in action: designer materialsmechanical behaviour

deformation and fracturestress, strainYoung modulusstiff, elastic, plastic, ductile, hard, brittle, toughstress-strain graphssize and spacing of particlesmetals, ceramics, polymers, composites

electrical behaviourmetals, semiconductors, insulatorsresistivity, conductivity

OCR B (Advancing Physics)

Unit 4 Rise and Fall of the Clockwork Universe

specific heat capacity

WJEC (Wales)

Unit 1 Motion, Energy and Chargedensity stored energyHooke’s lawfrictionviscosityresistivitysuperconductivity

Unit 2 Waves and Particlesrefractive index

WJEC (Wales)

Unit 4 Oscillations and Fields

stiffness (of a sample)specific heat capacity