igcse physics - student guide

8/11/2019 IGCSE Physics - Student Guide

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Revision Checklist for IGCSE

Physics 0625

A guide for Students


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Revision Checklist for IGCSE Physics 0625

A guide for students

How to use this guide

The guide describes what you need to know about your IGSCE Physics examination.

It will help you to plan your revision programme for the written examinations and will explainwhat the examiners are looking for in the answers you write. It can also be used to help youto revise by using the tick boxes in Section 3, What you need to know', to check what youknow and which topic areas of Physics you have covered.

The guide contains the following sections:

Section 1:How will you be tested?

This section will give you information about the different types of theory and practicalexamination Papers that are available.

Section 2: What will be tested?

This section describes the areas of knowledge, understanding and skills that the Examinerswill test you on. It is particularly important to realise that most marks are awarded forunderstanding and skills and only 25% of the total mark is for simple recall.

Section 3:What you need to know

This shows the syllabus in a simple way so that you can check

the topics you need to know about how the Extended syllabus (Supplement) differs from the Core syllabus details about each topic in the syllabus how much of the syllabus you have covered

Appendices

This section covers other things you need to know such as: symbols, units and definitions of physical quantities the importance of the command words the Examiners use in examination Papers information about the mathematical skills you need

Not all the information will be relevant to you. For example, you will need to select what youneed to know in Sections 1 and 3 by finding out from your teacher which examination Papersyou will be taking.

Section 1: How will you be tested?

1.1 The examination Papers you will take

You will be entered for threeexamination Papers, twotheory Papers and onepracticalPaper.


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You will need to ask your teacher which practical Paper you are taking. Nearer the time ofthe examination, you will also need to ask which theory papers you are being entered for.

If your teacher thinks that you should enter for the examination based on the Core syllabus,you will take Paper 1 (theory), Paper 2 (theory) and one of the practical Papers (4 or 5 or 6).

If your teacher thinks that you should enter for the examination based on the Extendedsyllabus, you will take Paper 1 (theory), Paper 3 (theory) and one of the practical Papers (4or 5 or 6).

Whether you take Paper 2 or 3 will depend on the progress your teacher thinks you havemade and which paper best suits your particular strengths. You should discuss this with yourteacher.

All students are assessed on practical work. This is by taking EITHER Paper 4 ORPaper 5 OR Paper 6. You should check with your teacher which paper you are to take.

1.2 About the theory Papers

The table gives you information about the theory Papers

Paper number How long and howmany marks?

What's in thePaper?

What's the % of thetotal examination?

Paper 1 45 minutes(40 marks)

40 multiple choicequestions. Youchoose one answeryou consider correctfrom 4 possibleanswers.

30%

Paper 2 1 hours(80 marks)

Short answer andstructured questions.You should writeyour answers in thespaces provided.The Paper teststopics in the Coresyllabus.

50%(you do eitherPaper 2 or

Paper 3)

Paper 3 1 hours(80 marks)

Short answer andstructured questions.You should writeyour answers in thespaces provided.The Paper teststopics in theExtended syllabus.

50%(you do eitherPaper 2 or

Paper 3)

Practical Paper see next table see next table 20%

Total 100%

1.3 About the practical Papers

Twenty percent of the marks for IGCSE Physics are for practical work. Practical work isbased only on the Core syllabus.


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You will do oneof the practical Papers shown in the table. Your teacher will tell you whichpractical Paper you will do. The number of marks varies between the Papers, but your finalmark will be calculated so it is worth the same percentage of the total examination as all theother practical Papers.

Paper number and type How long and how manymarks?

What's involved?

Paper 4(coursework)

no fixed time(48 marks)

You design and carry outexperiments, which are thenmarked by your teacher. Youwill be assessed on 4 skillareas. You need to produce2 pieces of work for eachskill area.

Paper 5(practical test)

1 hours(40 marks)

You do a practical examwhich is supervised by ateacher. You will carry out 4

short experiments.Paper 6

(alternative to practical)1 hour

(40 marks)You answer a written paperabout practical work. Thereare usually 5 questionswhich test the same skillareas as Paper 5.

The Practical Papers

Here is some more detail about each of the Practical Papers. If you are unsure of anything,ask your teacher.

1.3.1 Paper 4 (coursework)You will carry out several experiments throughout your Physics course, which will be markedby your teacher. Your teacher will mark you on 4 skill areas. What you have to do to get abasic (B), medium (M) or high (H) mark is shown below. You could use a highlighter pen, orunderlining, to note the differences between basic, medium and high.

Skill C1: Using apparatusYou follow written instructions to set up and use apparatus correctly. You carry out your worksafely.

B: You follow instructions correctly to do a single practical operation e.g. set up a simplecircuit and record the current.

You use familiar apparatus, with a little help on points of safety.

M: You follow instructions correctly to do a series of step-by-step practicaloperations, e.g. set up a circuit and record a series of voltage and current readings.You use familiar apparatus fairly well, with no help on points of safety.

H: You follow instructions correctly to do a series of step-by-step practicaloperations, but may need to change one step if things dont work out as youthought, e.g. use a wider range of loads to extend a spring a measurable amount.

You use familiar apparatus very well, with no help on points of safety.


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Skill C2: ObservingYou make observations and measurements and write them down clearly.

B: You make suitable observations when given some detailed instructions.You record results correctly when given a detailed table or some help.

M: You make suitable observations when given minimal instructions.You record results correctly when given an outline table or minimal help.

H: You make suitable observations without help and record results as accurately asthe apparatus allows.

You record results correctly without help.

Skill C3: Handling resultsYou draw graphs and/ or perform calculations from your results. You draw conclusions fromyour results and recognize any results, which do not fit into the pattern.

B:

You draw graphs (or do some calculations) from your results whengiven detailed suggestions.You draw simple conclusions from your results.

M: You draw graphs (or do some calculations) from your results whengiven only a little help.You draw simple conclusions from your results and comment on the patternsshown by the data, e.g. the extension of a spring is proportional to the load.You comment on results, which do not fit the pattern.

H: You draw graphs (or do some calculations) from your results whengiven no help.

You draw more general conclusions from your results and comment on thepatterns, e.g. the resistance of the wire increases with temperature.You comment on results which do not fit the pattern and suggest how to deal

with them, e.g. repeat a reading.You suggest what errors there are in your experiment.

Skill C4: Planning and evaluatingYou plan your experiment given some basic information from your teacher. You suggest howwell your plan worked and modify if necessary.

B: You write a simple plan for your experiment.You modify your plan after doing several experiments to see which works the

best.

M: You write a plan for your experiment, which has a series of logical steps in it.You modify your plan after doing trial experiments and give reasons why you

need to alter your original plan.If there are two variables (things which can change e.g. length of wire,diameter of wire), you recognise that one variable needs to be changed, whilethe other is kept the same, e.g. keep the diameter of the wire the same butvary the length.

H: You write a plan for your experiment which has a series of logical and clearly

reasoned steps.You modify your plan after doing trial experiments, give reasons why youneed to alter your original plan and suggest to what extent your plan works, and


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why. You suggest how to deal with unexpected results.If there are more than two variables, you recognise which needs to be controlled(kept constant) and which needs to be changed.

1.3.2 Paper 5 (Practical test)

You do a practical exam, which is supervised by a teacher. You are given an instructionsheet, which enables you carry out the experiments, handle the data and draw appropriateconclusions. You may be asked to use the following techniques:

recording current and potential difference and drawing circuit diagrams

ray tracing and drawing ray diagrams

measuring temperature

balancing (centre of mass and moments)

stretching of springs

timing of oscillations

1.3.3 Paper 6 (alternative to practical)

This is a written paper, testing the same four skills as Paper 5. You may be asked to:

record readings from diagrams of apparatus e.g. current readings

answer questions on the arrangement of apparatus

complete tables of data

draw conclusions from information

answer questions about experimental data

plot a graph from a table of readings

interpret information from graphs

draw ray diagrams

identify sources of error and suggest improvements in the experiment

suggest suitable apparatus for investigations

You will need to do plenty of practical work during the course in order to score a good markon this Paper in the examination.

Section 2: What will be tested?

The Examiners take account of the following areas in your examination Papers:

your knowledge (what you remember) and understanding (how you use what youknow and apply it to unfamiliar situations)

how you handle information and solve problems

your use experimental skills

These areas of knowledge and skills are called Assessment Objectives. The theory Paperstest mainly Objective A (knowledge with understanding) and Assessment Objective B(handling information and problem solving). You should note that only half the marksavailable for Assessment Objective A are for simple recall. The purpose of the practicalPaper is to test Assessment Objective C (experimental skills). Your teacher will be able to

give you more information about how each of these is used in examination Papers. The tableshows you the range of skills you should try to develop.


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Sk il l What the sk i ll means What you need to be ab le to

do

A:Knowledge with understanding

remembering factsand applying these

facts to new situations

1. use scientific ideas, factsand laws

2. know the meaning ofscientific terms e.g. centre ofmass3. know about apparatus andhow it works4. know about symbols,quantities (e.g. mass andweight) and units (e.g. kg andN)5. understand the importanceof science in

everyday life

B:Handling information andsolving problems

how you extractinformation andrearrange it in asensible pattern andhow you carry outcalculations and makepredictions

1. select and organizeinformation from graphs,tables and written text2. change information fromone form to another e.g. drawgraphs.3. arrange data and carry outcalculations4. identify patterns frominformation given and drawconclusions

5. explain scientificrelationships, e.g. use themoving (kinetic) particle theoryto explain ideas about solids,liquids and gases.6. make predictions anddevelop scientific ideas7. solve problems

C:experimental skills andinvestigations

planning and carryingout experiments andrecording andanalysing information

1. set up and use apparatussafely2. make observations andmeasurements and recordthem3. analyse experimentalresults and suggest how validthey are4. plan and carry out your ownexperiment anddescribe to what extent yourplan worked


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Section 3: What you need to know

This is a table, which describes the things you may be tested on in the examination. If youare studying only the Core syllabus (Papers 1 and 2), you will need to refer only to thecolumn headed Core material. If you are studying the Extended syllabus (Papers 1 and 3),

you will need to refer to both the Core material and the Extended material columns. If youare unsure about which material to use, you should ask you teacher for advice.

How to use the table

You can use the table throughout your course to check the topic areas you have covered.You can also use it as a revision aid. When you think you have a good knowledge of a topic,you can tick the appropriate box in the checklist column. The main headings in the topicareas are usually followed by the details of what you should know. Test yourself as follows: cover up the details with a piece of paper try to remember the details

when you have remembered the details correctly, put a tick in the appropriate box

If you use a pencil to tick the boxes, you can retest yourself whenever you want by simplyrubbing out the ticks. If you are using the table to check which topics you have covered, youcan put a tick in the topic column, next to the appropriate bullet point.

The column headed Comments can be used: to add further information about the details for each bullet point to add learning aids, e.g. simple equations set out in a triangle to help in rearranging theequation to highlight areas of difficulty/ things you need to ask your teacher about


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Topic

Core mater ial Extended mater ial

You sho uld be able to: Check l is t Comments You should be able to:

General PhysicsLength and time Use and describethe use of rules andmeasuring cylinders todetermine a length or avolume. Use and describethe use of clocks anddevices for measuringan interval of time.

Use and describe the useof a mechanical methodfor the measurement of asmall distance measureand describe how tomeasure a short intervalof time (including theperiod of a pendulum).

Speed, velocity andacceleration

Define speed andcalculate speed from

total distancetotal time

Plot and interpret aspeed/time graph or adistance/time graph Recognise from theshape of a speed/timegraph when a body is(a) at rest, (b) movingwith constant speed,(c) moving withchanging speed. Calculate the areaunder a speed/timegraph to determine thedistance travelled formotion with constantacceleration.

Distinguish betweenspeed and velocity

Recognise linearmotion for which theacceleration is constantand calculate theacceleration. Recognise motion forwhich the acceleration isnot constant. Describe qualitativelythe motion of bodiesfalling in a uniformgravitational field withand without air resistance(including reference toterminal velocity).


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Demonstrate someunderstanding thatacceleration is relatedto changing speed. State that the

acceleration of free fallfor a body near to theEarth is constant.

Mass and weight Show familiaritywith the idea of themass of a body. State that weight isa force. Demonstrateunderstanding thatweights (and hencemasses) may be

compared using abalance.

Demonstrate anunderstanding that massis a property whichresists change inmotion. Describe, and use theconcept of, weight as theeffect of a gravitationalfield on a mass.

Density Describe anexperiment todetermine the densityof a liquid and of aregularly shaped solidand make thenecessary calculation.

Describe thedetermination of thedensity of an irregularlyshaped solid by themethod of displacementand make the necessarycalculation.

Forces

(a) Effects of

forces

State that a force

may produce a changein size and shape of abody. Plot extension/loadgraphs and describethe associated

Interpret

extension/load graphs.State Hookes Law andrecall and use theexpression F = kx. Recognise thesignificance of the term


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experimentalprocedure. Describe the waysin which a force maychange the motion of a

body. Find the resultantof two or more forcesacting along the sameline.

limit of proportionality foran extension/load graph. Recall and use therelation between force,mass and acceleration

(including the direction). Describe,qualitatively, motion in acurved path due to aperpendicular force (F =mv2/r is not required).

(b) Turning effect Describe themoment of a force as ameasure of its turningeffect and give

everyday examples. Describe,qualitatively, thebalancing of a beamabout a pivot.

Perform and describean experiment (involvingvertical forces) to verifythat there is no net

moment on a body inequilibrium. Apply the idea ofopposing moments tosimple systems inequilibrium.

(c) Conditions forequilibrium

State that, when thereis no resultant forceand no resultantturning effect, a systemis in equilibrium.

(d) Centre of mass Perform anddescribe an experimentto determine theposition of the centre ofmass of a planelamina.


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the conversion ofenergy from one formto another and of itstransfer from one placeto another.

Apply the principleof energy conservationto simple examples.

(b) Energyresources

Describe howelectricity or otheruseful forms of energymay be obtained from(i) chemical energystored in fuel(ii) water, including the

energy stored inwaves, in tides and inwater behindhydroelectric dams

(iii) geothermalresources

(iv) nuclear fission

(v) heat and light fromthe Sun.

Show anunderstanding thatenergy is released bynuclear fusion in the Sun. Show a qualitativeunderstanding ofefficiency.

(c) Work Relate, withoutcalculation, work doneto the magnitude of aforce and distancemoved.

Describe energychanges in terms of workdone. Recall and use W =Fd = E.

(d) Power Relate, withoutcalculation, power to

Recall and use theequation P = E/t in simple


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work done and timetaken, usingappropriate examples.

systems.

Pressure Relate, withoutcalculation, pressure to

force and area, usingappropriate examples. Describe the simplemercury barometer andits use in measuringatmospheric pressure. Relate, withoutcalculation, thepressure beneath aliquid surface to depthand to density, usingappropriate examples.

Use and describethe use of amanometer.

Recall and use theequation p= F/A.

Recall and use theequation p= hg.

Thermal Physics

Simple kineticmolecular model ofmatter

(a) States of matter State the distinguishingproperties of solids,liquids and gases.

(b) Molecular

model

Describe

qualitatively themolecular structure ofsolids, liquids andgases. Interpret thetemperature of a gas in

Relate the properties

of solids, liquids andgases to the forces anddistances betweenmolecules and to themotion of the molecules. Show an appreciation


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terms of the motion ofits molecules. Describequalitatively thepressure of a gas in

terms of the motion ofits molecules. Describequalitatively the effectof a change oftemperature on thepressure of a gas atconstant volume. Show anunderstanding of therandom motion ofparticles in a

suspension asevidence for the kineticmolecular model ofmatter. Describe thismotion (sometimesknown as Brownianmotion) in terms ofrandom molecularbombardment.

that massive particlesmay be moved by light,fast-moving molecules.

(c) Evaporation Describe

evaporation in terms ofthe escape of more-energetic moleculesfrom the surface of aliquid. Relate evaporation

Demonstrate an

understanding of howtemperature, surfacearea and draught over asurface influenceevaporation.


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and the consequentcooling.

(d) Pressurechanges

Relate the changein volume of a gas tochange in pressure

applied to the gas atconstant temperature.

Recall and use theequationpV = constant atconstant temperature.

Thermal properties

(a) Thermalexpansion ofsolids, liquids andgases

Describequalitatively thethermal expansion ofsolids, liquids andgases. Identify and explainsome of the everydayapplications and

consequences ofthermal expansion. Describequalitatively the effectof a change oftemperature on thevolume of a gas atconstant pressure.

Show an appreciationof the relative order ofmagnitude of theexpansion of solids,liquids and gases.

(b) Measurement oftemperature

Appreciate how aphysical property whichvaries with temperaturemay be used for the

measurement oftemperature and stateexamples of suchproperties. Recognise theneed for and identify

Demonstrateunderstanding ofsensitivity, range andlinearity. Describe the structureof a thermocouple andshow understanding of itsuse for measuring hightemperatures and thosewhich vary rapidly.


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fixed points. Describe thestructure and action ofliquid-in-glassthermometers.

(c) Thermalcapacity

Relate a rise intemperature of a bodyto an increase ininternal energy. Show anunderstanding of theterm thermal capacity.

Describe anexperiment to measurethe specific heat capacityof a substance.

(d) Melting andboiling

Describe meltingand boiling in terms ofenergy input without achange in temperature. State the meaning

of melting point andboiling point. Describecondensation andsolidification.

Distinguish betweenboiling and evaporation Use the terms latentheat of vaporisation andlatent heat of fusion and

give a molecularinterpretation of latentheat. Describe anexperiment to measurespecific latent heats forsteam and for ice.

Transfer of thermalenergy

(a) Conduction Describeexperiments todemonstrate the

properties of good andbad conductors of heat.

Give a simplemolecular account of theheat transfer in solids.

(b) Convection Relate convectionin fluids to densitychanges and describeexperiments to


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illustrate convection.

(c) Radiation Identify infra-redradiation as part of theelectromagneticspectrum.

Describe experimentsto show the properties ofgood and bad emittersand good and bad

absorbers of infra-redradiation.

(d) Consequencesof energy transfer

Identify and explainsome of the everydayapplications andconsequences ofconduction, convectionand radiation.

Properties ofwaves, includinglight and sound

General waveproperties

Describe what ismeant by wave motionas illustrated byvibration in ropes,springs and byexperiments usingwater waves. Use the termwavefront. Give the meaningof speed, frequency,wavelength and

amplitude. Distinguishbetween transverseand longitudinal wavesand give suitableexamples.

Give the meaning ofthe term wavefront. Recall and use theequation v = f x. Interpret reflection,refraction and diffractionusing wave theory.


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Describe the use ofwater waves to show

(i) reflection ata planesurface

(ii) refractiondue to achange ofspeed

(iii) diffractionproduced bywide andnarrowgaps.

Light

(a) Reflection Describe theformation, and give the

characteristics, of theimage in a planemirror. Use the law angleof incidence = angle ofreflection.

Perform simpleconstructions,

measurements andcalculations.

(b) Refraction Describe anexperimentaldemonstration of therefraction of light. Use theterminology for the

angle of incidenceiand angle of refractionrand describe thepassage of lightthrough parallel-sidedtransparent material.

Recall and use thedefinition of refractiveindex n in terms of speed. Recall and use theequation sin i/sin r = n. Describe the action of

optical fibres.


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Give the meaningof critical angle. Describe internaland total internalreflection.

(c) Converginglenses

t

Describe the actionof a thin converginglens on a beam of light. Use the termsprincipal focus andfocal length. Draw ray diagramsto illustrate theformation of a realimage by a single lens.

Draw ray diagrams toillustrate the formation ofa virtual image by asingle lens. Use and describe theuse of a single lens as amagnifying glass.

(d) Dispersion oflight

Give a qualitativeaccount of thedispersion of light asillustrated by the actionon light of a glassprism.

(e)electromagneticspectrum

Describe the mainfeatures of theelectromagneticspectrum and state thatall e-m waves travel

with the same highspeed in vacuo.

State the approximatevalue of the speed ofelectromagnetic waves. Use the termmonochromatic.

Sound Describe theproduction of sound byvibrating sources. Describe the

Describecompression andrarefaction. State the order of


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longitudinal nature ofsound waves. State theapproximate range ofaudible frequencies.

Show anunderstanding that amedium is required inorder to transmit soundwaves. Describe anexperiment todetermine the speed ofsound in air. Relate theloudness and pitch ofsound waves to

amplitude andfrequency. Describe how thereflection of sound mayproduce an echo.

magnitude of the speedof sound in air, liquidsand solids.

Electricity andmagnetism

Simple phenomenaof magnetism

State the propertiesof magnets. Give an account ofinduced magnetism. Distinguishbetween ferrous andnon-ferrous materials. Describe methodsof magnetisation and ofdemagnetisation.


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Describe anexperiment to identifythe pattern of field linesround a bar magnet. Distinguish

between the magneticproperties of iron andsteel. Distinguishbetween the designand use of permanentmagnets andelectromagnets.

Electrical quantities

(a) Electric charge Describe simpleexperiments to show

the production anddetection ofelectrostatic charges. State that thereare positive andnegative charges. State that unlikecharges attract andthat like charges repel. Describe an electricfield as a region inwhich an electric

charge experiences aforce. Distinguishbetween electricalconductors andinsulators and give

State that charge ismeasured in coulombs.

State the direction oflines of force anddescribe simple fieldpatterns. Give an account ofcharging by induction. Recall and use thesimple electron model todistinguish betweenconductors andinsulators.


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typical examples.

(b) Current State that current isrelated to the flow ofcharge.

Use and describethe use of an ammeter.

Show understandingthat a current is a rate offlow of charge and recall

and use the equationI = Q/t.

Distinguish betweenthe direction of flow ofelectrons andconventional current.

(c) Electro-motiveforce

State that the e.m.f.of a source of electricalenergy is measured involts.

Show understandingthat e.m.f. is defined interms of energy suppliedby a source in driving

charge round a completecircuit.

(d) Potentialdifference

State that thepotential differenceacross a circuitcomponent ismeasured in volts. Use and describethe use of a voltmeter.

(e) Resistance State thatresistance = pd/current

and understandqualitatively howchanges in p.d. orresistance affectcurrent. Recall and use the

Recall and usequantitatively the

proportionality betweenresistance and the lengthand the inverseproportionality betweenresistance and cross-sectional area of a wire.


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equation R = V/I.

Describe anexperiment todetermine resistance

using a voltmeter andan ammeter. Relate (withoutcalculation) theresistance of a wire toits length and to itsdiameter.

(f) ElectricalEnergy

Recall and use theequation P = IVandE= Ivt.

Electrical circuits

(a) Circuit diagrams

Draw and interpretcircuit diagramscontaining sources,switches, resistors(fixed and variable),lamps, ammeters,voltmeters,magnetising coils,transformers, bells,fuses, relays.

Draw and interpretcircuit diagramscontaining diodes andtransistors.

(b) Series and

parallel circuits

Understand that the

current at every point ina series circuit is thesame. Give the combinedresistance of two ormore resistors in

Recall and use the

fact that the sum of thep.d.s. across thecomponents in a seriescircuit is equal to the totalp.d.s. across the supply. Recall and use the


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series. State that, for aparallel circuit, thecurrent from the sourceis larger than the

current in each branch. State that thecombined resistance oftwo resistors in parallelis less than that ofeither resistor by itself. State theadvantages ofconnecting lamps inparallel in a lightingcircuit.

fact that the current fromthe source is the sum ofthe currents in theseparate branches of aparallel circuit.

Calculate the effectiveresistance of tworesistors in parallel.

(c) Action and use

of circuitcomponents

Describe the action

of a variable potentialdivider (potentiometer). Describe the actionof thermistors and lightdependent resistorsand showunderstanding of theiruse as inputtransducers. Describe the actionof a capacitor as anenergy store and show

understanding of itsuse in time delaycircuits. Describe the actionof a relay and showunderstanding of its

Describe the action of

a diode and showunderstanding of its useas a rectifier. Describe the action ofa transistor as anelectrically operatedswitch and showunderstanding of its usein switching circuits. Recognise and showunderstanding of circuitsoperating as light

sensitive switches andtemperature operatedalarms (using a relay or atransistor).


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Electromagneticeffects

(a) Electromagneticinduction

Describe anexperiment whichshows that a changing

magnetic field caninduce an e.m.f. in acircuit.

State the factorsaffecting the magnitudeof an induced e.m.f.

Show understandingthat the direction of aninduced e.m.f. opposesthe change causing it.

(b) a.c generator Describe a rotating-coil generator and theuse of slip rings. Sketch a graph ofvoltage output against

time for a simple a.c.generator.

(c) Transformer Describe theconstruction of a basiciron-cored transformeras used for voltagetransformations. Recall and use theequation (Vp/Vs ) =(Np/Ns). Describe the use ofthe transformer in high-voltage transmission ofelectricity. Give theadvantages of high

Describe the principleof operation of atransformer. Recall and use theequation VpIp = VsIs(for100% efficiency). Discuss the energyloss in cables.


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voltage transmission.

(d) The magneticeffect of a current

Describe thepattern of the magneticfield due to currents instraight wires and in

solenoids. Describeapplications of themagnetic effect ofcurrent, including theaction of a relay.

State the qualitativevariation of the strengthof the magnetic field oversalient parts of the

pattern. Describe the effect onthe magnetic field ofchanging the magnitudeand direction of thecurrent.

(e) Force on acurrent-carryingconductor

Describe anexperiment to showthat a force acts on acurrent-carryingconductor in a

magnetic field,including the effect ofreversing (i) thecurrent, (ii) thedirection of the field.

Describe anexperiment to show thecorresponding force onbeams of chargedparticles.

State and use therelative directions offorce, field and current.

(f) d.c. motor State that acurrent-carrying coil ina magnetic fieldexperiences a turningeffect and that theeffect is increased byincreasing the number

of turns on the coil. Relate this turningeffect to the action ofan electric motor.

Describe the effect ofincreasing the current.


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Cathode rayoscilloscopes

(a) Cathode rays Describe theproduction anddetection of cathode

rays. Describe theirdeflection in electricfields. State that theparticles emitted inthermionic emissionare electrons.

(b) Simpletreatment ofcathode-ray

oscilloscope

Describe in outlinethe basic structure, andaction, of a cathode-ray

oscilloscope (detailedcircuits are not required). Use and describe theuse of a cathode-rayoscilloscope to displaywaveforms.

Atomic physics

Radioactivity

(a) Detection ofradioactivity

Show awareness ofthe existence ofbackground

radioactivity. Describe thedetection of -particles,-particles and -rays.

(b) Characteristics State that Describe their


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of the three kindsof emission

radioactive emissionsoccur randomly overspace and time. State, forradioactive emissions:

(i)their nature(ii)their relativeionising effects(iii) their relativepenetratingabilities.

deflection in electric fieldsand magnetic fields. Interpret their relativeionising effects.

(c) Radioactivedecay

State the meaningof radioactive decay,using equations(involving words orsymbols) to represent

changes in thecomposition of thenucleus when particlesare emitted.

(d) Half-life Use the term half-life in simplecalculations whichmight involveinformation in tables ordecay curves.

(e) Safetyprecautions

Describe howradioactive materials

are handled, used andstored in a safe way.

The nuclear atom

(a) Atomic model Describe thestructure of an atom interms of a nucleus and

Describe how thescattering of alpha-particles by thin metal


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electrons. foils provides evidencefor the nuclear atom.

(b) Nucleus Describe thecomposition of thenucleus in terms of

protons and neutrons. Use the termproton number (=atomic number), Z,usethe term nucleonnumber (=massnumber),A, use theterm nuclide andnuclide notation

AZ

X

(c) Isotopes Use the term isotope

Give and explainexamples of practicalapplications of isotopes


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SYMBOLS, UNITS AND DEFINITIONS OF PHYSICAL QUANTITIES

You should be able to state the symbols for the following physical quantities and, whereindicated, state the units in which they are measured. You should be able to define thoseitems indicated by an asterisk (*) The list for Extended includes both the Core and the

Supplement.CORE SUPPLEMENT

(for all students) (for students who are following the Extended Syllabus)

Quantity Symbol Unit Quantity Symbol Unit

length l, h ... km, m, cm, mm

area A m2, cm2

volume V m3, cm3

weight W N N*mass m, M kg, g mgtime t h, mm, s ms

density* g/cm3, kg/m3speed* a, v km/h, m/s, cm/s

acceleration a acceleration* m/s2

acceleration of

free fall g

force F, P ... N force* N*

moment of a force* N m

work done W, E J work done by a force* J*

energy E J J*, kW h*

power P w power* w*pressure p, P pressure* Pa*, N/m2

atmospheric pressure millibartemperature ,t oCspecific heatcapacity c J/(g oC), J/(kg oC) specific heat capacity*latent heat L J specific latent heat* l J/kg, J/g

frequency* f Hzwavelength* m, cm

focal length fangle of incidence i degree(o) refractive index nangle of reflection,refraction r degree(o)critical angle c degree(o)

potential

difference /voltageV V, mV potential difference* V*

current I A, mA current*

charge C, As

e.m.f E V e.m.f.*

resistance R

Command words and phrases used in physics papers


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Examiners use command words to help you to write down the answer they are looking for.This table explains what each of these words or phrases means and will help you tounderstand the kind of answer you should write. The list is in alphabetical order. You shouldbear in mind that the meaning of a term may vary slightly according to how the question isworded.

Calculate A numerical answer is needed. You should show any working,especially when there are two or more steps in a calculation.e.g. calculate the refractive index

Deduce This may be used in two ways:(i) You find the answer by working out the patterns in theinformation given to you and drawing logical conclusions fromthem. You may need to use information from tables and graphsand do calculations

e.g. deduce what will happen to velocity of the vehicle if .(ii) You have to refer to a Law or scientific theory or give a reason

for your answer

e.g. use your knowledge of the kinetic theory to deduce whatwill happen when

Define You need to state the meaning of somethinge.g. define speed

Describe You need to state the main points about something (using labelleddiagrams if it helps you).e.g. describe a rotating-coil generatorYou may also be asked to describeobservations e.g. describe the ways in which a force may changethe motion of a bodyhow to do particular experiments e.g. describe an experiment to

determine resistance using a voltmeter and an ammeter

Determine You are expected to use a formula or method that you know tocalculate a quantity.e.g. Determine graphically the resultant of two vectors

Discuss You have to write down points for and against an argumente.g. discuss the energy loss in cables

Estimate Suggest an approximate value for a quantity based on reasonsand data. You may need to make some approximations.e.g. estimate the volume of a test tube.

Explain You have to give reasons for your answerOR refer to a particular theory

Find This is a general term meaning several similar things such ascalculate, measure, determine etc.

List Write down a number of separate points. Where the number ofpoints is stated in the question, you should not write more than thisnumber.e.g. listthreeuses of converging lenses

Meant(what is meantby the term)

See Understand

Measure You are expected to find a quantity by using a measuringinstrumente.g. length (by using a ruler), volume (by using a measuring

cylinder)Outline State the main points briefly


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e.g. outline a method of magnetising an iron bar

Predict This can be used in two ways:(i) You find the answer by working out the patterns in theinformation provided and drawing logical conclusions from this. Youmay need to use information from tables and graphs and docalculations.

e.g. predict what will happen to the direction of the resultantforce if .(ii) It may also mean giving a short answer to a question statingwhat might happen next

e.g. predict what effect an increase in temperature will have onthe resistance.

Sketch (i) When drawing graphs, this means that you may draw theapproximate shape and/ or position of the graph BUT you need tomake sure that important details, such as the line passing throughthe origin or finishing at a certain point, are drawn accurately.(ii) When drawing apparatus or other diagrams, a simple linedrawing is all that is needed, but you must make sure that the

proportions are correct and the most important details are shown.You should always remember to label your diagrams.

State You should give a short answer without going into any detaile.g. state the hazards of damaged electrical insulationBUT: state the meaning of is different. It is more likeunderstand.

Suggest This may be used in two ways:(i) There may be more than one correct answer.

e.g. suggest a precaution to improve the accuracy of theexperiment(ii) You are being asked to apply your general knowledge of

physics or reasoning skills to a topic area that is not on the syllabuse.g. applying ideas about moments to the stability of a vehicle

Understand(what do youunderstand bythe term..)

You should (i) define something and (ii) make a more detailedcomment about it. The amount of detail depends on the number ofmarks awarded.e.g. what do you understand by the term total internal reflection


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The mathematical skills you need

This is a checklist of the mathematical skills you need for your physics exam.

Tick each box in the checklist when you know that you have got this skill.Ask your teacher to explain these skills if you are unsure. The comment column is for extra

notes and examples.

You can use a calculator for all the Papers. You should make sure that you remove anyinformation from your calculator, if it is programmable.

You can: checkl is t comments

add, subtract, multiply and divide

Use:

averages

decimals

fractions

percentages

ratios

reciprocals

recognise standard notation(notation is putting symbols fornumbers e.g. x = 2, y = 5,atomic mass, Z = 12)

use standard notation

use direct proportion(stepwise increases)

use inverse proportion(inverse means turned up sidedown)

You should know that if you plot agraph of yagainstx, then a straightline through the origin shows that yis directly proportional tox

the inverse of 4 is (= 0.25)

use numbers to the power of 10e.g. 1x10

2= 100

Your calculator will often shownumber to the power of 10 whenyou do calculations. Do not worrytoo much though your calculatordoes the work for you.

draw charts

graphs with line of best fitYou will be given the data


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igcse physics - student guide

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