Learner Guide for as and a Level Physics

7/27/2019 Learner Guide for as and a Level Physics

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Learner Guide for Cambridge AS and A Level Physics


How to use this guide

The guide describes what you need to know about your GCE Advanced Subsidiary (AS)and Advanced level Physics examination.

It will help you to plan your revision programme for the written examinations and will explain whatwe are looking for in the answers that you write. It will also help you to revise more effectively usingthe table given in Section 4, What do you need to know?.

The guide contains the following sections:

Section 1: How will you be tested?

This section gives you information about the written papers and practical tests that will be availablefor physics. It briefly describes the rules for Advanced Subsidiary (AS) and Advanced Levelcertifications. It contains a table that summaries the examination papers you will take and the

duration of each paper.

Section 2: Examination t ips

This section gives you advice to help you do as well as you can. Some of the tips are general advice andsome are based on the common mistakes that learners make in exams.

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Section 1: How will you be tested?

1.1 AS and A level Physics

Find out from your teacher what papers you are going to take.

If you have been entered for Advanced Subsidiary (AS) Physics, then you will be taking Papers 1, 2and 3 at a single examination session.

After having received AS certification, if you wish to continue your studies to the full Advanced Levelqualification, then your AS marks will be carried forward and you just take Papers 4 & 5 in theexamination session in which they require certification.

For the complete Advanced Level Physics qualification, you have to take all the papers in a singleexamination session.

1.2 Details about your examination papers

The table below gives you information about the Physics papers.

Paper How long is t he

paper and howmany marks?

What is in the papers? What is the

paper worthas apercentage of

the ASexamination?

What is the

paper worthas apercentage of

the A levelexamination?

Paper 1

Multiple-choice

1 hour

(40 marks)

The paper will have 40multiple-choice questionsall based on the ASsyllabus. You have to

ll

31% 15%


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Paper How long is t hepaper and howmany marks?

What is in the papers? What is thepaper worth

as apercentage of

the ASexamination?

What is thepaper worth

as apercentage of

the A levelexamination?

Paper 4

Structuredquestions(Core)

2 hours

(100 marks)

This paper will consist oftwo sections:Section A (70 marks)willconsist of questions basedon the A2 core, but may

include material firstencountered in the ASsyllabus.Section B (30 marks) willconsist of questions basedon Applications of Physics,but may include materialfirst encountered in thecore (AS and A2) syllabus.

Both sections will consistof a variable number ofstructured questions ofvariable mark value.Candidates will answer allquestions. Candidates willanswer on the questionpaper.

38%

Paper 5

P ti l T t

1 hour 15 min

(30 k )

This paper will consist of

t ti f l

12%


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Section 2: Examination t ips

How to Use These TipsThese tips highlight some common mistakes made by learners. They are collected under

various subheadings to help you when you revise a particular topic.

General Advice Dont give up if you think that you have calculated the answer to the first part of a question

incorrectly. You can still score marks for your follow on answers in the remaining parts of thequestion provided that your follow on calculations are correct.

Always show your working when answering a question. This will allow you to score marks

for your method, even if you make a mistake with the final answer. When you have calculated an answer always ask yourself if it is sensible and realistic.

If it isnt, go back and check your working.

Ensure that you are fully aware of what data and formulae are given at the front of the question

paper. Learn those formulae that are not given. During the examination you should monitor your rate of progression through the paper and

adjust your rate of working accordingly. This will ensure that towards the end of theexamination you will have sufficient time to complete the paper. Completing past papers

under timed conditions will allow you to develop an appropriate speed of working. Be careful with powers of 10 and take deliberate care if you are keying these into your

calculator; make sure that you do not neglect the minus sign of any negative powers andcheck that your final answer is reasonable.

All answers should have their correct unit. Pay particular attention to questions that ask youto give the units of your answer and so do not give a unit in the answer space.

Tips for Theory Papers

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definition; for example, pressure should be defined as force per unit area (notforce on unit area).

A non-numerical answer can sometimes be made clearer by adding a sketch, but

remember to ensure that it is clearly labelled and shows all the relevant information. Always give your answer to an appropriate number of significant figures. This can be judged

from the number of significant figures of the data given in the question.

Occasionally a question will tell you the number of significant figures that are to be used inyour answer and in this case your answer must have exactly the number of significant figuresspecified.

Do not prematurely round up figures at an intermediate stage during a calculation wait untilthe answer is reached and only then express it to an appropriate number of significant figures.

When doing algebra ensure that the terms on either side of an = sign do in fact equaleach other. It is bad practice to write down a string of terms all on the same line and allconnected by an = sign as any error can result in the first element being of an entirelydifferent nature and/or order to the last. This often leads to errors when calculating the totalresistance of a number of resistors connected in parallel.

Any explanations that you give should be as clear and precise as possible. Forexample, saying A increases as B increases would be insufficient if what is meant is A isproportional to B.

When substituting in the value of g use 9.81ms-2

(not 10ms-2

).

Paper 4: Section B

See the tips listed above for Papers 2 and 4.

Some questions may require you to give lengthy non-numerical answers. In such caseslook at how many marks are allocated to the question as this may help you to decide howmuch information to put into your answer. For example, if a question is worth 4 marks thenyou will need to include a minimum of 4 valid points in your answer (but more if you can).

Ensure that you read the question very carefully to establish exactly what information you areb i k d t l t A l ti f h i th t d t th ti ill


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All the raw readings of a particular quantity should be recorded to the same number of decimal

places which should in turn be consistent with the uncertainty in the readings. The uncertainty in a measurement can sometimes be larger than the smallest interval that can

be measured by the measuring equipment. For example, a stopwatch can measure time toa hundredth of a second, but human reaction times will mean that the uncertainty in thereading given by a stopwatch is (typically) 0.1s to 0.4s.

Each column heading in your table must contain both a quantity and its unit. For instanceif you have measured time t in seconds, your column heading would be written as t/s (tin s or t(s) would also be acceptable). The quantity or unit or both may also be written inwords rather than symbols.

The number of significant figures used in a derived quantity that you calculate from your rawreadings should be equal in number to (or possibly one more than) the number of significant

figures in the raw readings. For example, if you measure potential difference and currentto 2 and 3 sig figs respectively, then the corresponding value of resistance calculatedfrom them should be given to 2 or 3 sig figs, but not 1 or 4. If both were measured to 3significant figures, then the resistance could be given to 3 (or 4) sig figs.

When drawing your graph, do not forget to label each axis with the appropriate quantityand unit, using the same format for expressing column headings in a table. Choose a scalesuch that the plotted points occupy at least half the graph grid in both the x and y directions.The x-axis scale should increase positively to the right and the y-axis scale should increasepositively upwards. Use a convenient scale such as 1, 2 or 5 units to a 2cm square as you will

then be less likely to make a mistake with the position of your plotted points and it will beeasier for you to read off points from your graph if you are calculating the gradient or finding anintercept. Similarly, it is good practice to mark values on at least every other 2cm square.

All your plotted points should be on the grid; points in the white margin area will be ignored.Plot all your observations and ensure that they are accurate to half a small square. A finecross (or an encircled dot) drawn with a sharp pencil is acceptable, but be careful not toobscure the position of your points by your line of best fit or other working.

When drawing your line of best fit, ensure you have an even balance of points about the linealong its whole length. If it is a straight line, use a clear plastic rule so that you can see

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Paper 5 Tips: Practical Test

Planning Question

Do not panic if the context of the question appears unfamiliar to you. During your A Levelstudies you will have used or learnt about suitable apparatus for completing the task. If youare asked to use any unfamiliar apparatus the question will supply you with all the detailsthat you need to know about.

Read the question very carefully it may give you guidance on those aspects of your plan to

which you need to pay particular attention. It will also help you to identify the independent and

the dependent variables. When writing your answer you will need to consider some or all of the following:- what apparatus you will use- what experimental arrangement will be used

- what procedure will be followed- the independent and dependent variables- the means of keeping other variables constant - use the word constant

when identifying these variables, saying you will control them is insufficient- how the raw data readings will be processed to give the desired result, e.g. what

derived quantities you might calculate or what graph you might plot- what relevant safety precautions should be in place

The relationship to be tested, given to you in the introduction to the task, will

suggest the type of graph to be expected. You will need to describe it as

precisely as possible. For example, is it linear, does it pass through the origin? If

you choose a logarithmic graph, you will be expected to predict its slope from the

given expression.

When writing your answer you must write down all the information clearly and

explicitly - the examiner cannot give you marks for things that are vaguely implied.

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Evaluating data Question

See tips for Paper 3, where the comments regarding significant figures, plotting graphsand calculating gradients and intercepts apply equally for this paper..

It is particularly important that the rules, previously given for significant figures, are strictly adheredto.

You will be expected to use the uncertainty given in the raw data to find the uncertainty incalculated data. The latter will involve a function such as a logarithm. This requires plenty ofpractise, if you are to be able do it with confidence in the examination.

You will need to be able to translate the calculated uncertainties into error bars on your graph andthen to draw the worst acceptable line. Again, this requires plenty of practise.

Once the graph has been drawn, you will be expected to find uncertainties in both the gradient andthe intercept using your line of best fit and your worst acceptable line. A lot of marks depend onyour being able to calculate the uncertainties in the calculated data.

Every candidate is provided with the same data and so the final values calculated should be verysimilar. One mark is available to candidates who manage to work within a given tolerance,determined by the Principal Examiner.


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Section 3: What will be tested?

3.1 The assessment objectives

The areas of knowledge and skills are called Assessment Objectives. The theory papers test mainlyObjective A (Knowledge with understanding) and Assessment Objective B (Handling, applying andevaluating information). The practical papers are used to test you on the Assessment Objective C(Experimental skills and investigations). Your teacher will be able to provide you with more detailedinformation on the assessment objectives.

Assessment Object ive A: Knowledge w ith understanding

Questions testing these objectives will often begin questions with one of the following words:

Define State Describe Explain

Skill You should demonstrate knowledge and understanding of:

A1 Scientific phenomena Facts Laws Definitions Concepts Theories

A2 Scientific vocabulary Terminology


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Skill You should be able, in words or by using w ritten, symbolic, graphical andnumerical forms of presentation, to:

B5 Present reasoned explanations for

o phenomena

o patterns

o relationshipsB6 Make predictions and put forward hypotheses

B7 Apply knowledge, including principles, to new situations

B8 Evaluate information and hypotheses

B9 Demonstrate an awareness of the limitations of physical theories andmodels

Assessment Object ive C: Experimental ski lls and i nvest igations

Experiment skills are tested in the practical tests of papers 3 and 5.

Skill You should be able to:

C1

Follow a detailed set or sequence of instructions and use techniques,apparatus and materials safely and effectively

C2 Make observations and measurements with due regard for precision andaccuracy

C3 Interpret and evaluate observations and experimental data

C4 Identify a problem

Design and plan investigations

Evaluate methods and techniques and suggest possible improvement


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Cambridge International Examinations 2012

Section 4: What you need to know

The table below lists the things that you may be tested on in the examination.

You can use the table throughout your Physics course to check the topic areas you have covered. You can also use the table as a revision aid. You canmake notes to yourself as you go through the table in the comments column. These could be reminders like:

Need to go through some more questions on momentumSee the teacher about more questions on resistivity

or simply place a tick () in the comments column to show that you have a decent understanding of that particular physics.

Details of all the Options are also given. You must check with your teacher which of the Options you need to be prepared for.

Theme Topic You should b e able to Comments

I:GENERAL PHYSICS

Physical Quantities

and SI Units

Physical Quantities and

SI units

Show an understanding that all physical quantities consist

of a numerical magnitude and a unit. Recall the following base quantities and their units: mass

(kg), length (m), time (s), current (A), temperature (K),amount of substance (mol).

Express derived units as products or quotients of the baseunits and use the named units listed in this syllabus as

appropriate.

Use base units to check the homogeneity of physicalequations.

Show an understanding and use the conventions forlabelling graph axes and table columns as set out in theASE publication SI Units, Signs, Symbols andAbbreviations, except where these have been superseded


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Physical Quantities andSI units continued

Use the following prefixes and their symbols to indicatedecimal sub-multiples or multiples of both base and

derived units: pico (p), nano (n), micro (), milli (m), centi(c), deci (d), kilo (k), mega (M), giga (G), tera (T).

Make reasonable estimates of physical quantities includedwithin the syllabus.

The Avogadro constant Show an understanding of the significance of theAvogadro constant as the number of atoms in 0.012 kg ofCarbon-12.

Use molar quantities where one mole of any substance isthe amount containing a number of particles equal to theAvogadro constant.

Scalars and vectors Distinguish scalar and vector quantities and giveexamples of each.

Add and subtract coplanar vectors.

Represent a vector as two perpendicular components.

MeasurementTechniques

Measurements Use techniques for the measurement of length, volume,angle, mass, time, temperature and electrical quantitiesappropriate to the ranges of magnitude implied by therelevant parts of the syllabus. In particular, learnersshould be able to:

o

measure lengths using a ruler, vernier scale andmicrometer,o measure weight and hence mass using spring and

lever balances,o measure an angle using a protractor,o measure time intervals using clocks, stopwatches


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Measurementscontinued

and the calibrated time-base of a cathode-rayoscilloscope (c.r.o),

o measure temperature using a thermometer as asensor,

o use ammeters and voltmeters with appropriatescales,

o use a galvanometer in null methods,o use a cathode-ray oscilloscope (c.r.o),o use a calibrated Hall probe.

Use both analogue scales and digital displays. Use calibration curves.

Errors and uncertainties Show an understanding of the distinction betweensystematic errors (including zero errors) and randomerrors.

Show an understanding of the distinction betweenprecision and accuracy.

Assess the uncertainty in a derived quantity by simpleaddition of actual, fractional or percentage uncertainties (arigorous statistical treatment is not required).


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Theme Topic You should be able to Comments

II:NEWTONIANMECHANICS

Kinematics Linear motion Define displacement, speed, velocity and acceleration.

Use graphical methods to represent displacement, speed,velocity and acceleration.

Find displacement from the area under a velocity-timegraph.

Linear motioncontinued

Use the slope of a displacement-time graph to find thevelocity.

Use the slope of a velocity-time graph to find theacceleration.

Derive, from the definitions of velocity and acceleration,equations which represent uniformly accelerated motion ina straight line.

Solve problems using equations which represent uniformlyaccelerated motion in a straight line, including the motionof bodies falling in a uniform gravitational field without airresistance.

Recall that the weight of a body is equal to the product ofits mass and the acceleration of free fall.

Describe an experiment to determine the acceleration offree fall using a falling body.


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Non-linear motion Describe qualitatively the motion of bodies falling in auniform gravitational field with air resistance.

Describe and explain motion due to a uniform velocity inone direction and a uniform acceleration in aperpendicular direction.

Dynamics Newton's laws ofmotion

State each of Newton's laws of motion.

Show an understanding that mass is the property of abody which resists change in motion.

Describe and use the concept of weight as the effect of agravitational field on a mass.

Newton's laws ofmotion continued

Define linear momentum as the product of mass andvelocity.

Define force as rate of change of momentum.

Recall and solve problems using the relationship F = ma,appreciating that acceleration and force are always in thesame direction.


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Linear momentum andits conservation

State the principle of conservation of momentum.

Apply the principle of conservation of momentum to solvesimple problems including elastic and inelastic interactionsbetween two bodies in one dimension. (Knowledge of theconcept of coefficient of restitution is not required.)

Recognise that, for a perfectly elastic collision, the relative

speed of approach is equal to the relative speed ofseparation.

Show an understanding that, whilst momentum of asystem is always conserved in interactions betweenbodies, some change in kinetic energy usually takesplace.

Forces Types of force Describe the forces on mass and charge in uniformgravitational and electric fields, as appropriate.

Show an understanding of the origin of the upthrust actingon a body in a fluid.

Show a qualitative understanding of frictional forces andviscous forces including air resistance. (No treatment ofthe coefficients of friction and viscosity is required.)

Equilibrium of forces Use a vector triangle to represent forces in equilibrium.

Centre of gravity Show an understanding that the weight of a body may betaken as acting at a single point known as its centre ofgravity.


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Turning effects offorces

Show an understanding that a couple is a pair of forceswhich tends to produce rotation only.

Define and apply the moment of a force and the torque ofa couple.

Show an understanding that, when there is no resultant

force and no resultant torque, a system is in equilibrium. Apply the principle of moments.

Work, Energy, Power Energy conversion andconservation

Give examples of energy in different forms, its conversionand conservation, and apply the principle of energyconservation to simple examples.

Work Show an understanding of the concept of work in terms ofthe product of a force and displacement in the direction ofthe force.

Calculate the work done in a number of situationsincluding the work done by a gas which is expanding

against a constant external pressure: W = p V.

Potential energy, kineticenergy and internalenergy

Derive, from the equations of motion, the formula Ek =mv

2.

Recall and apply the formula Ek = mv2.

Distinguish between gravitational potential energy, electricpotential energy and elastic potential energy.


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Potential energy, kineticenergy and internalenergy continued

Show an understanding and use the relationship betweenforce and potential energy in a uniform field to solveproblems.

Derive, from the defining equation W = Fs, the formula Ep

= mgh for potential energy changes near the Earth'ssurface.

Recall and use the formula Ep = mgh for potential energychanges near the Earth's surface.

Show an understanding of the concept of internal energy.

Power Show an appreciation for the implications of energy lossesin practical devices and use the concept of efficiency tosolve problems.

Define power as work done per unit time and derive power

as the product of force and velocity.

Motion in a Circle Kinematics of uniformcircular motion

Express angular displacement in radians.

Understand and use the concept of angular velocity tosolve problems.

Recall and use =rto solve problems.

Centripetal acceleration Describe qualitatively motion in a curved path due to aperpendicular force, and understand the centripetalacceleration in the case of uniform motion in a circle.

Recall and use centripetal acceleration a = r2

a = 2/r.

Centripetal force Recall and use centripetal forceF = m r

2, F = m2/r.


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Gravitational Field Gravitational field Show an understanding of the concept of a gravitationalfield as an example of field of force and definegravitational field strength as force per unit mass.

Force between pointmasses

Recall and use Newton's law of gravitation in the formF = G(m1m2)/r

2

Field of a point mass Derive, from Newton's law of gravitation and the definition

of gravitational field strength, the equation g =GM

for ther2

gravitational field strength of a point mass.

Recall and solve problems using the equation g =GM

forr2

the gravitational field strength of a point mass.

Recognise the analogy between certain qualitative andquantitative aspects of gravitational field and electric field.

Analyse circular orbits in inverse square law fields byrelating the gravitational force to the centripetalacceleration it causes.

Show an understanding of geostationary orbits and theirapplication.

Field near to thesurface of the Earth

Show an appreciation that on the surface of the Earth g isapproximately constant and is called the acceleration offree fall.

Gravitational potential Define potential at a point as the work done in bringingunit mass from infinity to the point.

Solve problems using the equation = GM

for ther

potential in the field of a point mass.


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III:MATTER

Phases of Matter Density Define the term density

Solids, liquids, gases Relate the difference in the structures and densities of

solids, liquids and gases to simple ideas of the spacing,ordering and motion of molecules.

Describe a simple kinetic model for solids, liquids andgases.

Describe an experiment which demonstrates Brownianmotion and appreciate the evidence for the movement ofmolecules provided by such an experiment.

Distinguish between the structure of crystalline and non-crystalline solids with particular reference to metals,polymers and amorphous materials.

Pressure in fluids Define the term pressure and use the kinetic model toexplain the pressure exerted by gases.

Derive, from the definitions of pressure and density, theequation p =gh.

Use the equation

p =gh.

Change of phase Distinguish between the processes of melting, boiling and

evaporation.

Deformation ofSolids

Stress, strain Appreciate that deformation is caused by a force and that,in one dimension, the deformation can be tensile orcompressive.

Describe the behaviour of springs in terms of load,extension, elastic limit, Hookes law and the springconstant (i.e. force per unit extension).


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Stress, straincontinued

Define and use the terms stress, strain and the Youngmodulus.

Describe an experiment to determine the Young modulusof a metal in the form of a wire.

Elastic and plasticbehaviour

Distinguish between elastic and plastic deformation of amaterial.

Deduce the strain energy in a deformed material from thearea under the force-extension graph.

Demonstrate knowledge of the force-extension graphs fortypical ductile, brittle and polymeric materials, including anunderstanding of ultimate tensile stress.

Ideal Gases Equation of state Recall and solve problems using the equation of state for

an ideal gas expressed as pV = nRT. (n =number ofmoles)

Kinetic theory of gases Infer from a Brownian motion experiment the evidence forthe movement of molecules.

State the basic assumptions of the kinetic theory of gases.

Pressure of a gas Explain how molecular movement causes the pressureexerted by a gas and hence deduce the

relationship,

(N =number of molecules)

[A rigorous derivation is not required.]

P = 13mV


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Kinetic energy of amolecule

Compare

with pV = NkT and hence deduce that the average

translational kinetic energy of a molecule is proportional toT.Temperature Thermal equilibrium Show an appreciation that thermal energy is transferred

from a region of higher temperature to a region of lowertemperature.

Show an understanding that regions of equal temperatureare in thermal equilibrium.

Temperature scales Show an understanding that there is an absolute scale oftemperature which does not depend on the property ofany particular substance (i.e. the thermodynamic scaleand the concept of absolute zero).

Convert temperatures measured in kelvin to degrees

Celsius:T / K= T / C + 273.15.

Practical thermometers show an understanding that a physical property whichvaries with temperature may be used for the measurementof temperature and state examples of such properties.

Compare the relative advantages and disadvantages ofresistance and thermocouple thermometers as previouslycalibrated instruments.

PV=1

3Nm


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Thermal Propertiesof Materials

Specific heat capacity Explain using a simple kinetic model for matter whyo melting and boiling take place without a change in

temperature,o the specific latent heat of vaporisation is higher

than specific latent heat of fusion for the samesubstance,

o a cooling effect accompanies evaporation.

Define and use the concept of specific heat capacity, andidentify the main principles of its determination byelectrical methods.

Specific latent heat Define and use the concept of specific latent heat, andidentify the main principles of its determination byelectrical methods.

Internal energy Relate a rise in temperature of a body to an increase in its

internal energy.

Show an understanding that internal energy is determinedby the state of the system and that it can be expressed asthe sum of a random distribution of kinetic and potentialenergies associated with the molecules of a system.

First law ofthermodynamics

Recall and use the first law of thermodynamics expressedin terms of the change in internal energy, the heating ofthe system and the work done on the system.


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IV:OSCILLATIONS AND

WAVES

Oscillations Simple harmonicmotion

Describe simple examples of free oscillations.

Investigate the motion of an oscillator using experimentaland graphical methods.

Understand and use the terms amplitude, period,frequency, angular frequency and phase difference andexpress the period in terms of both frequency and angularfrequency.

Recognise and use the equation a = -2x as the defining

equation of simple harmonic motion.

Recall and use

x = x0sint as a solution to the equation a = -2x

Simple harmonicmotion continued Recognise and use v = v0cost and

Describe with graphical illustrations, the changes in

displacement, velocity and acceleration during simple

harmonic motion.


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Energy in simpleharmonic motion

Describe the interchange between kinetic and potentialenergy during simple harmonic motion.

Damped and forcedoscillations: resonance

Describe practical examples of damped oscillations withparticular reference to the effects of the degree ofdamping and the importance of critical damping in casessuch as a car suspension system.

Describe practical examples of forced oscillations andresonance.

Describe graphically how the amplitude of a forcedoscillation changes with frequency near to the naturalfrequency of the system, and understand qualitatively thefactors which determine the frequency response andsharpness of the resonance.

Show an appreciation that there are some circumstancesin which resonance is useful and other circumstances in

which resonance should be avoided.

Waves Progressive waves Describe what is meant by wave motion as illustrated byvibration in ropes, springs and ripple tanks.

Show an understanding and use the terms displacement,amplitude, phase difference, period, frequency,wavelength and speed.


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Deduce, from the definitions of speed, frequency andwavelength, the equation

= f.

Recall and use the equation = f.

Show an understanding that energy is transferred due to aprogressive wave.

Recall and use the relationship, intensity (amplitude)2.

Transverse andlongitudinal waves

Compare transverse and longitudinal waves.

Analyse and interpret graphical representations oftransverse and longitudinal waves.

Polarisation Show an understanding that polarisation is a phenomenonassociated with transverse waves.

Determination of speed,frequency andwavelength

Determine the frequency of sound using a calibrated c.r.o.

Determine the wavelength of sound using stationarywaves.

Electromagneticspectrum

State that all electromagnetic waves travel with the samespeed in free space and recall the orders of magnitude ofthe wavelengths of the principal radiations from radio wavesto -rays.

Superposition

Stationary waves

Explain and use the principle of superposition in simpleapplications.

Show an understanding of experiments whichdemonstrate stationary waves using microwaves,stretched strings and air columns.

Explain the formation of a stationary wave using agraphical method, and identify nodes and antinodes.

id f b id d l h i


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Diffraction Explain the meaning of the term diffraction.

Show an understanding of experiments whichdemonstrate diffraction including the diffraction of waterwaves in a ripple tank with both a wide gap and a narrowgap.

Interference Show an understanding of the terms interference andcoherence.

Two-sourceinterference patterns

Show an understanding of experiments whichdemonstrate two-source interference using water, lightand microwaves.

Show an understanding of the conditions required if two-source interference fringes are to be observed.

Recall and solve problems using the equation = ax / Dfor double-slit interference using light.

Diffraction grating Recall and solve problems using the formula d sin= nand describe the use of a diffraction grating to determinethe wavelength of light. (The structure and use of thespectrometer is not included.)

L G id f C b id AS d A L l Ph i


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V:ELECTRICITY ANDMAGNETISM

Electric Fields Concept of an electricfield

Show an understanding of the concept of an electric fieldas an example of a field of force and define electric fieldstrength as force per unit positive charge.

Represent an electric field by means of field lines.

Uniform electric fields Recall and use E =V/d to calculate the field strength ofthe uniform field between charged parallel plates in termsof potential difference and separation.

Calculate the forces on charges in uniform electric fields.

Describe the effect of a uniform electric field on the motionof charged particles.

Force between pointcharges

Recall and use Coulomb's law in the formF = Q1Q2/4or2

for the force between two point charges in free space orair.

Electric field of a pointcharge

Recall and use = or2 for the field strength of aopoint charge in free space or air.

Recognise the analogy between certain qualitative andquantitative aspects of electric field and gravitationalfields.



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Electric potential Define potential at a point in terms of the work done inbringing unit positive charge from infinity to the point.

State that the field strength of the field at a point isnumerically equal to the potential gradient at that point.

Use the equation

V = Q/4orfor the potential in the field of a point charge.

Capacitance Capacitors andcapacitance

Show an understanding of the function of capacitors insimple circuits.

Define capacitance and the farad.

Recall and solve problems using

C = Q/V.

Capacitors andcapacitance continued

Derive, using the formula C = Q/V, conservation of chargeand the addition of p.ds, formulae for capacitors in seriesand in parallel.

Solve problems using formulae for capacitors in seriesand in parallel.

Energy stored in acapacitor

Deduce from the area under a potential-charge graph, theequation W =QV and hence W = CV

2.

Current of Electricity Electric current Show an understanding that electric current is the rate offlow of charged particles.

Define charge and the coulomb.

Recall and solve problems using the equation Q = It.



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Potential difference Define potential difference and the volt.


V =W/Q.

Recall and solve problems using P = VI, P = I2R.

Resistance andresistivity

Define resistance and the ohm.

Recall and solve problems using V =IR.

Sketch and explain the I-V characteristics of a metallicconductor at constant temperature, a semiconductor diodeand a filament lamp.

Sketch the temperature characteristic of a thermistor.

State Ohm's law.

Recall and solve problems using R =l/A.

Sources ofelectromotive force

Define e.m.f. in terms of the energy transferred by asource in driving unit charge round a complete circuit.

Distinguish between e.m.f. and p.d in terms of energyconsiderations.

Show an understanding of the effects of the internalresistance of a source of e.m.f. on the terminal potentialdifference and output power.



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D.C. Circuits Practical circuits Recall and use appropriate circuit symbols as set out in SIUnits, Signs, Symbols and Abbreviations (ASE, 1981) andSigns, Symbols and Systematics (ASE, 1995).

Draw and interpret circuit diagrams containing sources,switches, resistors, ammeters, voltmeters, and/or any

other type of component referred to in the syllabus Show an understanding of the use of a potential divider

circuit as a source of variable p.d.

Explain the use of thermistors and light-dependentresistors in potential dividers to provide a potentialdifference which is dependent on temperature andillumination respectively.

Conservation of chargeand energy

Recall Kirchhoff's first law and appreciate the link toconservation of charge.

Recall Kirchhoff's second law and appreciate the link toconservation of energy.

Derive, using Kirchhoff's laws, a formula for the combinedresistance of two or more resistors in series.

Solve problems using the formula for the combinedresistance of two or more resistors in series.

Conservation of chargeand energy continued

Derive, using Kirchhoff's laws, a formula for the combinedresistance of two or more resistors in parallel.

Solve problems using the formula for the combinedresistance of two or more resistors in parallel.

Apply Kirchhoff's laws to solve simple circuit problems.

Balanced potentials Recall and solve problems using the principle of thepotentiometer as a means of comparing potentialdifferences.



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Magnetic Fields Concept of magneticfield

Show an understanding that a magnetic field is anexample of a field of force produced either by current-carrying conductors or by permanent magnets.

Represent a magnetic field by field lines.

Electromagnetism Force on a current-carrying conductor

Show an appreciation that a force might act on a current- carrying conductor placed in a magnetic field.

Recall and solve problems using the equation F = BIl sin,with directions as interpreted by Fleming's left-hand rule.

Define magnetic flux density and the tesla.

Show an understanding of how the force on a current-carrying conductor can be used to measure the fluxdensity of a magnetic field using a current balance.

Force on a movingcharge

Predict the direction of the force on a charge moving in amagnetic field.


F = BQv sin.

Magnetic fields due tocurrents

Sketch flux patterns due to a long straight wire, a flatcircular coil and a long solenoid.

Show an understanding that the field due to a solenoidmay be influenced by the presence of a ferrous core.

Force between current-carrying conductors

Explain the forces between current-carrying conductorsand predict the direction of the forces.

Describe and compare the forces on mass, charge andcurrent in gravitational, electric and magnetic fields, asappropriate.



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g y



ElectromagneticInduction

Laws ofelectromagneticinduction

Define magnetic flux and the weber.


= BA.

Define magnetic flux linkage.

Infer from appropriate experiments on electromagneticinduction:

o that a changing magnetic flux can induce an e.m.f.in a circuit,

o that the direction of the induced e.m.f. opposes thechange producing it,

o the factors affecting the magnitude of the inducede.m.f.

Recall and solve problems using Faraday's law ofelectromagnetic induction and Lenz's law.

Explain simple applications of electromagnetic induction.



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Alternatin g Cur rent s Characteristics ofalternating currents

Show an understanding and use the terms period,frequency, peak value and root-mean-square value asapplied to an alternating current or voltage.

Deduce that the mean power in a resistive load is half themaximum power for a sinusoidal alternating current.

Represent a sinusoidally alternating current or voltage by

an equation of the form

x = xosint .

Distinguish between r.m.s. and peak values and recall andsolve problems using the relationshipIRMS= I0/ 2 for the sinusoidal case.

The transformer Show an understanding of the principle of operation of asimple iron-cored transformer and solve problems using

Ns/Np =Vs/Vp =Ip /Is

for an ideal transformer.

Transmission ofelectrical energy

Show an appreciation of the scientific and economicadvantages of alternating current and of high voltages forthe transmission of electrical energy.

Rectification Distinguish graphically between half-wave and full-waverectification.

Explain the use of a single diode for the half-waverectification of an alternating current.

Explain the use of four diodes (bridge rectifier) for the full-wave rectification of an alternating current.

Analyse the effect of a single capacitor in smoothing,including the effect of the value of capacitance in relationto the load resistance.



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VI:MODERN PHYSICS

Charged Particles Electrons Show an understanding of the main principles ofdetermination ofe by Millikan's experiment.

Summarise and interpret the experimental evidence forquantisation of charge.

Beams of chargedparticles

Describe and analyse qualitatively the deflection of beamsof charged particles by uniform electric and uniformmagnetic fields.

Explain how electric and magnetic fields can be used invelocity selection.

Explain the main principles of one method for thedetermination ofv and e/me for electrons.

Quantum Physics Energy of a photon Show an appreciation of the particulate nature of

electromagnetic radiation.

Recall and use E = hf.

Photoelectric emissionof electrons

Show an understanding that the photoelectric effectprovides evidence for a particulate nature ofelectromagnetic radiation while phenomena such asinterference and diffraction provide evidence for a wavenature.

Recall the significance of threshold frequency.

Explain photoelectric phenomena in terms of photonenergy and work function energy.

Explain why the maximum photoelectric energy isindependent of intensity whereas the photoelectric currentis proportional to intensity.



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Photoelectric emissionof electrons continued

Recall, use and explain the significance of

hf = + mv 2 .max

Wave-particle duality Describe and interpret qualitatively the evidence providedby electron diffraction for the wave nature of particles.

Recall and use the relation for the de Broglie wavelength

= h/p.

Energy levels in atoms Show an understanding of the existence of discreteelectron energy levels in isolated atoms (e.g. atomichydrogen) and deduce how this leads to spectral lines.

Line spectra Distinguish between emission and absorption line spectra.

Recall and solve problems using the relation hf = E1 - E2.

Nuclear Physic s The nucleus Infer from the results of the -particle scatteringexperiment the existence and small size of the nucleus.

Describe a simple model for the nuclear atom to includeprotons, neutrons and orbital electrons.

Distinguish between nucleon number (mass number) andproton number (atomic number).

Isotopes Show an understanding that an element can exist invarious isotopic forms each with a different number ofneutrons.

Use the usual notation for the representation of nuclides.



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Nuclear processes Appreciate that nucleon number, proton number, andenergy and mass are all conserved in nuclear processes.

Represent simple nuclear reactions by nuclear equationsof the form14N+ 4He 17O +1H.7 2 8 1

Show an appreciation of the spontaneous and random

nature of nuclear decay.

Show an understanding of the nature of-, - and -radiations.

Infer the random nature of radioactive decay from thefluctuations in count rate.

Mass excess andnuclear binding energy

Show an appreciation of the association between energyand mass as represented by E =mc

2and by recalling this

relationship.

Sketch the variation of binding energy per nucleon withnucleon number.

Explain the relevance of binding energy per nucleon tonuclear fusion and to nuclear fission.

Radioactive decay Define the terms activity and decay constant and recalland solve problems usingA =N.

Infer and sketch the exponential nature of radioactivedecay and solve problems using the relationship

x = xoexp(-t)where x could represent activity, number of undecayedparticles or received count rate.



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Radioactive decaycontinued

Define half-life.

Solve problems using the relation =

0.693

t12

VII:Gathering andcommunicatinginformation.Direct Sensing Sensing devices show an understanding that an electronic sensor

consists of a sensing device and a circuit that provides anoutput voltage

show an understanding of the change in resistance withlight intensity of a light-dependent resistor (LDR)

sketch the temperature characteristic of a negativetemperaturecoefficient thermistor

show an understanding of the action of a piezo-electric

transducer and its application in a simple microphone describe the structure of a metal-wire strain gauge relate extension of a strain gauge to change in resistance of

the gauge show an understanding that the output from sensing

devices can be registered as a voltage

The ideal operationalamplifier

Operational amplifiercircuits

recall the main properties of the ideal operational amplifier(op-amp)

deduce, from the properties of an ideal operationalamplifier, the use of an operational amplifier as a

comparator show an understanding of the effects of negative feedback

on the gain of an operational amplifier recall the circuit diagrams for both the inverting and the

non-inverting amplifier for single signal input show an understanding of the virtual earth approximation

and derive an expression for the gain of inverting amplifiers

recall and use expressions for the voltage gain of inverting



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Outputdevices

and of non-inverting amplifiers show an understanding of the use of relays in electronic

circuits show an understanding of the use of light-emitting diodes

(LEDs) as devices to indicate the state of the output ofelectronic circuits

show an understanding of the need for calibration where

digital or analogue meters are used as output devices.

Remote sensing

Production and useof X-rays

explain in simple terms the need for remote sensing (non-invasive techniques of diagnosis) in medicine

explain the principles of the production of X-rays by electronbombardment of a metal target

describe the main features of a modern X-ray tube, includingcontrol of the intensity and hardness of the X-ray beam

show an understanding of the use of X-rays in imaging

internal body structures, including a simple analysis of thecauses of sharpness and contrast in X-ray imaging show an understanding of the purpose of computed

tomography or CT scanning

show an understanding of the principles of CT scanning show an understanding of how the image of an 8-voxel cube

can be developed using CT scanningProduction and useof ultrasound

explain the principles of the generation and detection ofultrasonic waves using piezo-electric transducers

explain the main principles behind the use of ultrasound to

obtain diagnostic information about internal structures

show an understanding of the meaning of specific acousticimpedance and its importance to the intensity reflectioncoefficient at a boundary

recall and solve problems by using the equation I =I0exfor

the attenuation of X-rays and of ultrasound in matter



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Use of magneticresonance as animaging technique

explain the main principles behind the use of magneticresonance to obtain diagnostic information about internalstructures

show an understanding of the function of the non-uniformmagnetic field, superimposed on the large constant magnetic

field, in diagnosis using magnetic resonance

Communicatinginformation

Principles ofmodulation

understand the term modulation and be able to distinguishbetween amplitude modulation (AM) and frequencymodulation (FM)

Sidebands andbandwidth

recall that a carrier wave, amplitude modulated by a singleaudio frequency, is equivalent to the carrier wave frequencytogether with two sideband frequencies

understand the term bandwidth demonstrate an awareness of the relative advantages of AM

and FM transmissions

Transmission ofinformation bydigital means

recall the advantages of the transmission of data in digitalform, compared to the transmission of data in analogue form

understand that the digital transmission of speech or musicinvolves analogue-to-digital conversion (ADC) ontransmission and digital-to-analogue conversion (DAC) on

reception show an understanding of the effect of the sampling rate and

the number of bits in each sample on the reproduction of aninput signal



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Different channels ofcommunication

appreciate that information may be carried by a number ofdifferent channels, including wire-pairs, coaxial cables, radioand microwave links and optic fibres

discuss the relative advantages and disadvantages ofchannels of communication in terms of available bandwidth,noise, crosslinking, security, signal attenuation, repeatersand regeneration, cost and convenience

describe the use of satellites in communication recall the relative merits of both geostationary and polar

orbiting satellites for communicating information. recall the frequencies and wavelengths used in different

channels of communication understand and use signal attenuation expressed in dB and

dB per unit length. recall and use the expression number of

dB = 10lgP1

P2 for the ratio of two powers

The mobile-phonenetwork

understand that, in a mobile-phone system, the publicswitched telephone network (PSTN) is linked to base stationsvia a cellular exchange

understand the need for an area to be divided into a numberof cells, each cell served by a base station

understand the role of the base station and the cellularexchange during the making of a call from a mobile phonehandset

recall a simplified block diagram of a mobile phone handsetand understand the function of each block.

Documents

Learner Guide for as and a Level Physics