Physics for Yoou

7/25/2019 Physics for Yoou

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What is the use of a book, thought Alice, without pictures or conversations?

Lewis Carroll, Alice in Wonderland

Everything should be made as simple as possible, but not simpler.

Albert Einstein

There is no higher or lower knowledge, but one only, flowing out of experimentation.

Leonardo da Vinci

I do not know what I may appear to the world, but to myself I seem to have beenonly a boy playing on the seashore, and diverting myself in now and then finding asmoother pebble or a prettier shell than ordinary, while the great ocean of truth lay

ll d d b f

Keith and Ann Johnson 1978, 1980, 1986, 1991, 2001, 2006, 2011

The right of Keith Johnson to be identified as author of this work has been asserted by him inaccordance with the Copyright, Designs and Patents Act 1988.

All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means,electronic or mechanical, including photocopy, recording or any information storage and retrieval system,without permission in writing from the publisher or under licence from the Copyright Licensing Agency Limited,of Saffron House, 610 Kirby Street, London EC1N 8TS. Any person who commits any unauthorised act in relation tothis publication may be liable to criminal prosecution and civil claims for damages.

This edition published in 2011 by: Nelson Thornes Ltd, Delta Place, 27 Bath Road, CHELTENHAM, GL53 7TH, United Kingdom

ISB N 97 8 1 40 85 09 22 7 1 1 12 1 3 14 1 5 / 1 0 9 8 7 6 5 4 3 2 1

A catalogue record for this book is available from the British Library

Page make-up by Tech-Set with additional typesetting by Fakenham Photosetting

Printed and bound in China by 1010 Printing International Ltd

Website:

The website at www.physicsforyou.co.ukgives you details of exactly which pages

in this book you need to study for your particular GCSE examination course.

Make sure you visit this website and print out the correct sections.

They will show you:

which topics you need to learn for your particular examination, and

which page numbers to read in this book.


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Introduction

Physics For You is designed to introduce youto the basic ideas of Physics, and show you how

these ideas can help to explain the world in whichwe live.

This book is based on successful earlier editionsof the same name, but new pages and extraquestions have been added to cover the latestrequirements of the new GCSE Examinations.

Physics For You has been designed to beinteresting and to help you to pass your exams,

whether you are using it for a Physics course oras part of a Core Science or Additional Sciencecourse.

The book is carefully laid out so that each newidea is introduced and developed on a single pageor on two facing pages. Words have been kept toa minimum and as straightforward as possible.Pages with ared bandin the top corner are the

more difficult pages and may be left out at first.Throughout the book there are many simpleexperiments for you to do. A safety sign:means your teacher should give you furtheradvice (for example, to wear safety glasses).

Each important fact or new formula is printed inheavy typeor is in a box. There is a summary ofimportant facts at the end of each chapter.

At the back of the book there is advice for youon practical work, key skills, ideas and evidence

in science, careers, revision and examinationtechniques, as well as help with mathematics.

Questions at the end of a chapter range fromsimple fill-in-a-missing-word sentences (useful forwriting notes in your notebook) to more difficultquestions that will need some more thought.In calculations, simple numbers have been used tokeep the arithmetic as straightforward as possible.

At the end of each main topic you will find asection of further questions taken from actualGCSE examination papers.

Throughout the book, cartoons and rhymes areused to explain ideas and ask questions for you toanswer. In many of the cartoons, Professor Messermakes a mistake because he does not understandPhysics very well. Professor Messer does not think

very clearly, but I expect you will be able to see hismistakes and explain where he has gone wrong.

Here I would like to thank my wife, Ann, for herconstant encouragement and her help with themany diagrams and cartoons.

I hope you will find Physics interesting as well asuseful. Above all, I hope you will enjoyPhysicsFor You.

Keith Johnson

!

Professor Messer gets in messes,Things go wrong when he makes guesses.


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1 How Science works 62 Units 83 Energy 104 Molecules 16

Basic ideas

Contents

The Andromeda galaxy It contains about

5 Expansion 216 Thermometers 267 The Gas Laws 298 Measuring Heat 359 Conduction, Convection, Radiation 40

Physics at work: Keeping warm 43

10 Changing State 53Further questions on heat 60

Heat (thermal energy)

11 Pushes and Pulls 6412 Density 7413 Pressure 77

14 More about Forces 82Physics at work: Friction 83Physics at work: Parachutes 89

15 Turning Forces 9016 Work, Energy and Power 97

Physics at work: Supplying electricity 10517 Machines 11618 Velocity and Acceleration 122

Physics at work: Sport 134

19 Momentum 136Further questions on mechanics 140

Mechanics

20 The Earth and beyond 146Physics at work: Satellites 154Ph i t k S t l 160

Earth Physics and Astronomy

Seven atoms in a uranyl microcrystal, photographedwith an electron microscope and false colour added.They are magnified 100 million times.

. . . and the large.

The small . . .


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21 Waves 16622 Light 17123 Reflection 17624 Curved Mirrors 18125 Refraction 184

Physics at work: Fibre optics 192Physics at work: Lasers 19326 Lenses 19427 Optical instruments 19828 Colour 206

Physics at work: Electromagnetic waves212Physics at work: Telescopes in space 215Physics at work: Mobile phones 216Physics at work: Analogue and digital 218

29 Sound 224Physics at work: Ultrasonic echoes 228Further questions on waves 236

Waves: Light and Sound

30 Static Electricity 241

Physics at work: Static electricity 24631 Circuits 24832 Heating Effect of a current 264

Physics at work: Circuit-breakers 27233 Chemical Effect of a current 273

Further questions on Electricity (1) 276

34 Magnetism 280Physics at work: Magnets 284

35 Magnetic Effect of a current 286Physics at work: Using electromagnets288

36 Electromagnetic Induction 296Physics at work: In your home 306

37 Electron beams 308Physics at work: In the office 314

38 Electronics 316Ph i t k R di 331

Electricity and Magnetism

39 Radioactivity 338Physics at work: Radioactive dating 352Further questions on radioactivity 353Physics at work: Medical physics 356

Nuclear Physics

How Science works 358Doing Your Coursework 366

How scientists work 370

Ideas changing over time 371Famous Names 376History of Inventions 378

Extra sections

Key Skills 380

Careers using Physics 388

Check your Maths 390

Answers 392

Index 396

Revision Techniques 382Revision Programme 384Revision Checklist 385

Examination Technique 386


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chapter 1

The main purpose of this book is to help you gainscientific knowledge and understanding.But you also need to know How Science works,and how scientists work.

You will learn a lot of this by planning and then

doing your own experiments and investigations,to collect data (see the opposite page).

How scientists work

The purpose of Science is to find out how the Universe works.We are trying to explain the world in which we live.We do experiments and investigations to observe and collectevidence, rather like detectives investigating a crime.

From the evidence scientists try to form a theory orthought-model, to explain the evidence.(For example, the kinetic theory of molecules on page 16.)

A good theory or model is one which can be used to makea prediction, which we can test by experiment.If the experiment contradicts it, then the theory is modifiedor changed to a new theory that fits the facts ...until newevidence disproves this theory, and so on.

In this way, human understanding of our world hasdeveloped step by step. This is how Science works.

The history of Science shows how scientific ideas havechanged step by step (see pages 371379).

In the modern world, scientists usually work in teams andshare their ideas with other teams, by publishing them inbooks or on the internet (see page 370 for more details).

It is vital that their evidence is reliable and valid. It is then forsociety as a whole to make decisions based on that evidence.For example, what to do about global warming (see page 107).

Of course there are many questions that Science cannot answeryet (eg. how to cure all cancers). And there are questions thatScience can never attempt to answer (eg. religious questions).

How Science works

As Albert Einstein said:No amount of experimentation canever prove me right; but a singleexperiment may prove me wrong.

Practical skills are important

Science can explainhowwesee a flower, ...but it cannotexplain whyit looks beautiful.


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Read through the box below, and discuss any difficult words inyour group or with your teacher. See also the Glossary below.Make sure that you understand all of the words.

Glossary

Data: a series of measurements, used as evidence.

Variables These are things that you can vary or changeduring your investigation. There are 3 main types: independent(or input) variable. This is the thing that

youdecide to change. dependent(or outcome) variable. This is the variable that

changes as a result. It is the variable that you measure. control variables. These are all the variables that must not

change, so that it is a fair test.

Reliable evidence is data that we can trust. If someone elsedid the same experiment would they find the same evidence?Your evidence will be more reliable if you repeat the readings.

Validevidence is data that measures what you intended, andis directly relevant to your investigation.

Secondary evidence is data collected by someone else.Y fi d it i b k th i t t b t h ld

For example: VariablesWhen you stretch an elastic band,- the independent variable is the force

that you apply,- the dependent variable is the length of

the elastic (which you can measure).

For example: ReliableMeasuring the time of a pendulum

more than once, and taking an average,gives you more reliable data.

For example: ValidMeasuring the volume of food is not validevidence of the amount of energy in it.

For example: Secondary dataData on road safety published by a car

Science is a powerful tool for answering certain questions.To do this we need to plan an investigation to collect data.We can do this by observing andmeasuring. Usually weare trying to find a link between 2 variables.

When planning an investigation we always try to make it afair test. We need to ensure that the data we collect arereliableand valid. As well as the primary data that wecollect, we can also use secondary data.

For some investigations we can use ICT, either to takemeasurements (using asensor) or to model the situation.

When we have collected data, we need to present it clearly,in order to see anypatterns in the data. We can usetables, bar-chartsandline-graphsto display the data.

On a line-graph we can draw a line of best fit. This lets ussee anyanomalousdata that do not fit the pattern.The line of best fit may allow us to draw a conclusion.

We should always evaluate our work. This means: evaluating the investigation to see if it could be improved, evaluating our data to see if they are reliablea nd valid.

Plan yourinvestigation

Observe andmeasure the data

Present your datain tables, charts

or line-graphs

Analyse the data,and try to

draw a conclusion

Evaluate the dataand the investigation

The main steps

in an investigation


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chapter 2

Length

Length is measured in a unit called the metre(often shortened to m).A door knob is usually about 1 metre from theground; doorways are about 2 m high.

We often use centimetres (100 cm = 1 metre)or millimetres (1000 mm = 1 metre).

To measure short lengths very accurately wecan use vernier calipers or a micrometer.

When measuring in Physics we try to do it asaccurately as we can.

Professor Messer is trying to measure the lengthof a block of wood with a metre rule but he hasmade at least six mistakes.

How many mistakes can you find?

Experiment 2.2Measure the length of a block of wood taking

Experiment 2.1a) Look at a metre rule. Which marks are centi-

metres and which are millimetres?b) It is useful to know the length of your hand-

span. Mine is 22 cm (0.22 m); what is yours?c) Use the metre rule to measure

the length of your foot your height.Write down your answers in mm and also in m.


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Mass

If you buy a bag of sugar in a shop, you will findthe mass of sugar marked on the bag. It is written

in grams (g) or in kilograms (kg). Kilo alwaysmeans a thousand, so 1 kilogram = 1000 grams.

The mass of this book is about 1 kilogram.People often get confused between mass and weight,but they are notthe same (see pages 65 and 68).

Time

In Physics, time is always measured in seconds(sometimes shortened to s).You can count seconds very roughly, without awatch, by saying at a steady rate: ONE (thousand)TWO (thousand) THREE (thousand) FOUR . . .

All the other units you will meet in this book arebased on the metre, the kilogram and the second.They are called SI units.

Very large and small numbers

For very large or very small numbers, we some-times use a shorthand way of writing them, by

counting the number of zeros (see also page 391).For example:

a) 1 million = 1 000 000 (6 zeros) = 106

b) 2 million = 2 000 000 = 2 106

c) 0.000 001 =1 001

0 000 (1 millionth) = 106

In this shorthand way, write down:

Experiment 2.3Lift some masses labelled 1 kg, 2 kg, 5 kg and 1 g.

!

Experiment 2.4Use a stopclock or stopwatch to measure thetime for a complete swing of apendulum (seepage 99) or the beating of your heart.What is the time for 100 of your heartbeats?What is the time for one heartbeat?By how much does it change if you run upstairs?

!

In Maths and in Physics, a kMeans a thousand of whatever you say

For grams and for metresAnd even, for teachers,The size of their annual pay.

Mega (M) = 1 mill ion =1 000000kilo (k) = 1 thousand = 1 000

centi (c) = 1 hundredth = 1

1

00

milli (m) = 1 thousandth =10

1

00

micro () = 1 millionth =1 00

1

0 000

nano (n) = 1 thousand-millionth =1 000 0

100 000

kilo is not the only prefix:

Approximate Events

length of time

in seconds1018 Expected lifetime of the Sun

1017 Age of the Earth

1015 Time since the dinosaurs lived

1013 Time since the earliest human

1010 Time since Isaac Newton lived

109 Average human life span

107 A school term

105 One day

100 One second

102 Time for sound to cross a room

107 Time for an electron to travel

down a TV tube

108 Time for light to cross a room

1011 Time for light to pass through

spectacles

1022 Time for some events inside


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chapter 3

Energy can exist in different forms, as you can see in the cartoon.

People get their energy from the chemical energyin their food.

Cars run on the chemical energy in petrol. A firework in the cartoon

has chemical energy which it transforms tothermal energy (heat)and lightandsound energy when it explodes.

Some forms of energy a re calledpotential energy.One kind of potential energy is the elastic energy(also calledstrain energy) stored in the stretched elastic of a catapult.The bucket over the door also has some stored potential energy,called gravitational potential energy. When the bucket fallsdown, this gravitational energy is transferred to movement energy.

The moving pellets from the catapult and the moving people all havemovement energy, calledkinetic energy.

The television set is taking in electrical energyand transferring itto thermal energy and light and sound energy.

Another form of energy isnuclear energy, which is used in nuclearpower stations.

I wish I could find some use for all that energy!


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The connecting lines on the diagram show the different ways

that energy can be changed from one form to another.See if you can decide what the energy changes a re in the following objects.

For example:A firework changeschemical energy to thermal energy, lighta nd soundenergy.Copy and complete these sentences.

1. A TV set changes . . . . . . . . . . . . . . . . . . energy to . . . . . . . . . energy.2. A match changes . . . . . . . . . . . . . . . . . . energy to . . . . . . . . . energy.

3. A light-bulb changes . . . . . . . . . . . . . . . . energy to . . . . . . . . . energy.4. A catapult changes . . . . . . . . . . . . . . . . . energy to . . . . . . . . . energy.5. A falling bucket changes . . . . . . . . . . . . energy to . . . . . . . . . energy.6. An electric fire changes . . . . . . . . . . . . . energy to . . . . . . . . . energy.7. A human body changes . . . . . . . . . . . . . energy to . . . . . . . . . energy.8. A microphone changes . . . . . . . . . . . . . energy to . . . . . . . . . energy.9. An atomic bomb changes . . . . . . . . . . . energy to . . . . . . . . . energy.

10 A car engine changes energy to energy


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Energy changes

In the diagram on the previous page (page 11), one energy change hasbeen labelled electric fire. Copy out the diagram into your book andthen add the correct label to every arrow. Use words from the followinglist: coal fire, electric fire, steam engine, atom bomb (on four arrows),car engine, battery, loudspeaker, dynamo, very hot object, friction,bow and arrow, falling parachutist, cricket ball rising in the air,vibrations, microphone, thermocouple, solar cell, solar panel,plants, glow-worm, fluorescent lamp, girl landing on a trampoline,hanging a weight on a spring, an arm muscle tightening, sound-absorbing material, electroplating.

Saving money

Energy costs money and we use large amounts ofenergy/money each day.There are several ways of saving energy/money inyour home (and making your home more comfort-able at the same time). The table shows the timetaken before they have paid for themselves andstart to show a profit.

How well is your home insulated?How well is your school insulated? Write a list ofrecommendations.

Energy is measured in units calledjoules.The joule is a small unit. To lift this book througha height of 10 cm needs about 1 joule.When you walk upstairs you use over 1000 joules.

The diagram below shows the energy (in joules)involved in different events.(Remember: 105 = number with 5 zeros = 100 000and 105 = 100

1

000)

Taking in chemical energy

Method Payback times*

Lagging the hot- Less than a month

water cylinder

Draught excluders A few weeks

Lagging the loft About 3 years

(see page 43).

Wall cavity 4 7 yearsinsulation

Double glazing About 10 years

in windows

*all these times areshorter if you get agovernment grant

kinetic energy ofan alpha-particle

energy from

uranium atom

energy neededto lift ahairthrough1 mm

moonlight onyourfacefor1second

energy to liftthisbook from

kinetic energyofabullet

energy fromacompletelyburnt match

1kfor1hour(1 kW h)

dayswork fora woodcutt er


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Power stations are wasteful (see p. 104).The overall efficiency (from power

station to your home) is about 25 %.Three-quarters of the energy isentirely wasted! The wasted energycould be used to heat nearby homes.

The energy crisis

We are only just beginning to realise fully that our planet Earth is aspaceship withlimitedfood and fuel (and we are taking on morepassengers each year as the population increases).

Our supplies of energy cannot last for ever.

Oil a nd natural gas will be the first to disappear. If the whole worldused oil at the rate it is used in America and Europe, our oil supplieswould end in about 4 years! They are non-renewable.As it is, the worlds oil supplies might last for about 40 years.

How old will you be then? In what ways will your life be differentwithout oil (and therefore without petrol and plastics) ?

Natural gas will last a bit longer perhaps 60 years.Coal will last longer perhaps 300 years with careful mining.

Nuclearenergy might help for a while but it causes problems dueto the very dangerous radioactive waste that is produced (page 350).Also, each power station lasts only about 30 years and is difficult todismantle because of the radioactivity.

Wewaste huge amounts of energy. It takes over 5 million joules ofenergy to make one fizzy-drink-can and we throw away 700 millionof them each year! Making paper and steel uses particularly largeamounts of energy, but very little is recycled.

Wemustfind new ways of obtaining energy. The Suns energy isfree but it is not easy to capture it. Governments are looking fornew sources of energy (see next page). They will probably not give

enough energy for the future. Our main hope is that the H-bombfusion process (page 156) will eventually be controlled. Energy sources of Britain at present.What will happen when thefossil fuels (oil, gas, coal) run out ?

renewable2%nuclear9%

COAL

17%OIL

32%

NATURAL

GAS

40%


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Renewable sources of energy

Some sources of energy are renewable. They are notused up like coal or oil.Physicists and engineers are working hard to developbetter machines to use these sources of energy.

Solar energy

The Earth receives an enormous amount of energydirectly from the Sun each day, but we use verylittle of it. Some homes have solar panels on theroof (see page 50). In hot countries solar ovens

can be used for cooking (see page 48) and forproducing electricity insolar thermal towers.

Space ships and satellites use solar cells toconvert sunlight into electricity. You may haveseen calculators powered by solar cells.

Covering part of the Sahara Desert with solar cellswould produce energy but would be very expensive.To equal the power of one modern power station

you would need 40 square kilometres of solar cells.

Biomass

Some of the sunlight shining on the Earth is trappedby plants, as they grow. We use this biomasswhen we eat plants or when we burn wood.

In Brazil they grow sugar cane and then use the

sugar to make alcohol (bio-ethanol).The alcohol is then used in cars, instead of petrol.

Rotting plants can produce a gas called methanewhich is the same as the natura l gas we use forcooking. If the plants rot in a closed tank, called adigester, the gas can be piped away and used asfuel for cooking. This is often used in India.

Wind energy

This energy also comes from the Sun, because windsare caused by the Sun heating different parts ofthe Earth unequally.

Modern wind-generators are very efficient butit takes about 2000 very large wind turbines to

Source of energy Original source

Solar Sun

Biomass Sun

Wind Sun

Waves Sun

Hydro-electric Sun

Tides Moon

Geothermal Earth

manure and

rotting plants

methane gas

digester

gas


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Wave energy

Waves are caused by the winds blowing across the sea.They contain a lot of free energy.

One method of getting this energy is to use large floatswhich move up and down with the waves.The movement energy can be converted to electricity.However, we would need about 20 kilometres of floatsto produce as much energy as one power station.

Hydro-electric energy

Dams can be used to store rain-water, and then thefalling water can be used to make electricity (see

experiment 16.5 on page 101).

This is a very useful and clean source of energy formountainous countries like Norway and China.

The same idea can be used to store energy from powerstations that cannot easily shut down. At night, whendemand is low, spare electricity can be used to pumpwater up to a high lake. During the day, the water canbe a llowed to fall back down, to produce electricitywhen it is needed.

Tidal energy

As the Moon goes round the Earth it pulls on the seasso that the height of the tide varies.

If a dam is built across an estuary, it can have gateswhich trap the water at high tide. Then at low tide,

the water can be allowed to fall back through thedam and make electricity (see experiment 16.5).

Geothermal energy

The inside of the Earth is hot (due to radioactivity,see chapter 39). In some parts of the world (like NewZealand) hot water comes to the surface naturally. Inother countries cold water is pumped down very deepholes and steam comes back to the surface.

oceanwaves pivot

float rocks up and down

A pumped storage scheme in Scotland

A tidal power station in France

Summary

Energy exists in several different forms:

chemical, electric, magnetic, kinetic, potential(elastic and gravitational), sound, nuclear,electromagnetic radiation (including light)

d th l (i t l

Energy can be changed from one form to another.

Some sources of energy are non-renewable andwill be used up: coal, oil, gas, nuclear.Other sources are renewable: solar, biomass,

i d h d l t i tid l d th l

upper lake

lower lake

large powerstation insidethe mountain

400m


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A

absolute temperature 27, 31absolute zero 27, 31, 34a.c. 268, 2989, 317a.c. generator 298300acceleration 1225, 127, 1301acceleration due to gravity

1289, 131

accuracy 362acoustics 234air bag 138air resistance 87, 89alpha-particle 3402, 345, 350alpha-particle scattering 342alternating current 268, 2989,

317AM (amplitude modulation) 331ammeter 250

ampere 250, 260ampre-hour 115amplifier 322, 325amplitude 167, 231analogue 2189, 306

AND gate 3269anode 2734, 308asteroids 152atmospheric pressure 57, 80atomic mass 343atomic structure 342

atoms 3423, 372

B

background radiation 340, 350balance 75

spring 667balloon, hot-air 45barometer, mercury 80

battery 115, 252, 260Becquerel, Henri 338, 350, 372bell, electric 288beta-particle 3401, 345Big-Bang theory 158, 373bi-metallic strip 23, 25, 272biomass 14biometrics 356black hole 157, 372b ili 57

Boyles Law 29, 33, 34braking 79, 83bridges 22, 73Brownian movement 18

C

calorific value 35camera, lens 1956, 1989

pinhole 174capacitor 245, 317, 325car, brakes 79, 83

cooling system 44driving mirror 182engine 11415, 116headlamp 183

ignition system 304safety 69, 83, 138starter motor 289, 292

carbon capture 107careers 3889cathode 2734, 308, 316cathode-ray oscilloscope 31011cathode rays 309CD-ROM 218, 306, 314cell, dry 252, 260Celsius (centigrade) 26, 27

centre of mass (gravity) 925, 134centripetal force 701, 134, 148, 153chain reaction 348change of state 537charges, law of force 241Charles Law 301, 33, 34chemical effect of a current 2735circuit-breaker 269, 272, 295circuits, parallel 251, 257, 261

ring main 26870

series 250, 256, 261circular motion 701, 134, 148, 153clinical thermometer 27cloud chamber 338collisions 1378colour-blindness 203, 221colours, primary 221, 307, 311

secondary 221comets 152

i ti 155 192 211

compact disc (CD, DVD) 218, 306,314

computer 314concave mirror 48, 1812conduction, of electricity 243, 249

of heat 403conductors 41, 243, 249conservation of energy 98, 102,

371continental drift 373convection 38, 40, 445, 51, 264

convex mirror 1813copper, refining of 275coulomb 245, 2601critical angle 187CRO (oscilloscope) 232, 31011, 317crumple zones 69, 138current : voltage graphs 259, 316curved mirrors 1813

Ddating, radioactive 347, 352deceleration 122decibel 230, 234defects, of hearing 230, 234

of vision 2023demagnetisation 281density 746, 78, 147depth of field or focus 199diffraction 155, 169, 211, 226, 228

diffusion 19digital 21819, 306, 314, 326diode 308, 31617, 321, 331dispersion 2067displacement 126distancetime graph 126Doppler effect 158dosemeter 214, 350double-glazing 43d 298 300

Index


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Eear 230Earth 48, 71, 14655, 282earthing 26870

earthquakes 1467electrocardiography (ECG) 356echoes 226, 2289eclipse 173eddy currents 302efficiency 1023, 116

of machines 1023, 116, 11819, 302Einstein, Albert 348, 372, 374, 376elastic (strain) energy 10, 98, 108elastic limit 66electric bell 288

electric energy 10, 1046, 261, 2667electric field 244electric fire 38, 264electric force 17, 241electric lamp 103, 212, 259, 265electric motor 2903electric power 111, 266electricity, generating 1046, 296303electricity meter 2678electrolysis 2735

electromagnet 281, 2879electromagnetic induction 296303electromagnetic waves 20715electron 242, 249, 2601, 30812electronics 31629electroplating 2745electroscope, gold-leaf 243, 338electrostatic induction 242electrostatic precipitator 246e.m.f. 252endoscope 192

energy, and work 97, 99, 108chemical 10, 35, 98electrical 10,98, 1046, 261, 2667heat (thermal) 10, 358, 98, 101kinetic 10, 989, 109, 137, 224light 10, 98, 101nuclear 10, 13, 98, 3489potential 10, 989, 1089renewable sources of 14, 1036sound 10, 98, 22434

unit of 358, 979, 110, 2667energy crisis 13, 1047, 349energy transfers 11, 12, 98, 1004energy transfer diagrams 1024, 116equations of motion 127equilibrium 93evaporation 56examinations 3867expansion, of gases 24, 30

f li id 24

F

f-number 199farad 245Faraday, Michael 274, 297, 375, 377

feedback 324fibre optics 189, 192, 218, 314field, electric 244

gravitational 131, 149, 153magnetic 282, 2867, 290

filter 220fission, nuclear 348Flemings left-hand rule 290Flemings right-hand rule 296floating 87fluorescence 210, 212, 265

flux, magnetic 282FM (frequency modulation) 331focal length, of lenses 1945

of mirrors 181focus, principal 181, 194force 6571, 827, 97, 130, 136

balanced 847, 89, 128centripetal 701, 134, 148, 153electric 17, 241gravitational 657, 97, 131, 149,

153moment of 90parallelogram of 86

free-body force diagram 87freezing point 27, 54, 57frequency 167, 232friction 823, 89, 116, 134fuel cell 115fuse 26870fusion (melting) 53

nuclear 13, 98, 152, 156, 349

Ggalaxy 1579gamma-rays 208, 210, 214, 341, 347gas laws 2934gases 1618, 24, 2934gears 118Geiger 339, 342

generator, a.c. 298300d.c. 300Van de Graaff 244

geo-stationary orbit 154, 155global warming 107gold-leaf electroscope 243, 338gravitational field 131, 149, 153gravitational potential energy 11, 108gravity 657, 85, 89, 128, 131, 153

h ff t 48 106 7 150

Hhalf-life 344, 352heat, and temperature 26

energy 10, 358, 1001

measurement of 358unit of 358, 97

heat exchanger 44, 348heat pump 56heating effect of current 264hertz 167Hookes Law 66hot-water system 44hovercraft 82how Science works 67, 35870Hubbles Law 158, 373

hybrid car 115hydraulic brakes 79hydroelectric power 15, 101, 1056hydrogen bomb 13, 98, 156hydrogen fuel cell 115

Iideas and evidence 3589, 3709

illusions, optical 201, 203images, curved mirror 1812in lenses 1946, 198plane mirror 178real 174, 195, 198

virtual 179immersion heater 50, 264inclined plane 118induced charges 242induced current 296305induction, electromagnetic 296303

electrostatic 242magnetic 283

inertia 689infra-red rays 40, 4651, 209, 211,

213, 214ink-jet printer 315insulation 12, 413, 51internal combustion engine 114internal energy 26, 356inventions 3789

inverse square law 153, 214, 217, 341ion 244, 274, 338ionisation 244, 338, 346ionosphere 211isotope 343, 346

J

j t i 114


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KKelvin scale 27, 31Key Skills 3767kilogram 9, 68, 130

kilowatt-hour 267kinetic energy 10, 989, 109, 137kinetic theory of gases 16, 34Kirchhoffs Law 251

Llamp, electric 103, 212, 259, 265laser 193, 306laser printer 315latent heat, of fusion 534

of vaporisation 55LDR 192, 319, 324, 329LED 192, 265, 318left-hand rule, Flemings 290lenses 1946, 198Lenzs Law 297levers 90, 117light-dependent resistor 192, 319, 324light waves 169, 171, 207, 208

light-year 1578, 171lightning 227, 245lines of force (flux) 282, 2867logic gates 3269longitudinal waves 146, 166, 225loudness 230, 232, 234loudspeaker 291

M

machines 11620magnetic effect of a current 286magnetic field 282, 2867, 289

due to a coil, solenoid 287magnetic induction 283magnetic line of force (flux) 282magnetic materials 283magnetism, Earths 282

induced 283theory of 283

magnification 195magnifying glass 196mains, house circuit 265, 26870Maltese cross tube 309manometer 80mantle, Earths 146mass 9, 68, 130

critical 348mass number 343

th ti 390 1

melting point 57and impurities 57and pressure 57

meteors 152microphone 289, 291, 297, 301

microscope 196microwaves 209, 211, 213, 21617microwave oven 213mirage 189mirror, concave 48, 1812

convex 1812plane 1769

mobile phones 2167, 314molecules 16, 18, 24, 26, 34, 41, 53,

56, 73, 80, 149, 225, 227, 283moments, principle of 901

momentum 1368Moon 65, 71, 131, 149, 173motor, electric 2903MRI imaging 357multiplexing 219

Nnear Earth objects (NEOs) 152

nebula 152, 157neutral point 282neutron 3423neutron star 157newton 67, 130Newton, Sir Isaac 65, 69, 84, 130,

206, 372, 374, 376Newtons First Law 6970, 128Newtons Second Law 1301, 136Newtons Third Law 845, 160

noise 219, 234NOT gate 327nuclear energy 10, 13, 98, 348nuclear equations 345nuclear fission 3489nuclear fusion 13, 98, 152, 156, 349nuclear reactor 104, 3489nucleon 343nucleus 242, 342nuclide 343, 345, 346

Oersted, Hans Christian 286ohmic conductor 253, 259Ohms Law 2535, 259optical fibre 189, 192, 218, 314OR gate 3269oscilloscope 232 310 11 317

Pparachute 89, 128parallel circuits 251, 257, 261parallelogram of forces 86

pascal 77pendulum 9, 99penumbra 1723period, periodic time 167periscope 177persistence of vision 201PET scanning 357photocopier 315pitch of sound 232plane mirror 1769planets 1501, 152

plug, three-pin 270polarised waves 167pole, magnetic 280positron 357potential difference 2523, 261potential divider 258, 318, 323, 329potential energy 10, 989, 1089potentiometer 258power 11011, 135, 2667power station 1315, 101, 1046, 349

pressure 7781atmospheric 80pressure cooker 57pressure gauges 80pressure law 324principal focus 181, 194prism, refraction by 207

totally reflecting 188projector, optical 196, 204proton 242, 3423pulleys 119

pulse oximetry 356

Qquality of sound 233

Rradar 211, 311

radiation, alpha, beta 340, 345dangers of 214, 21617, 350gamma 208, 210, 214, 341, 345, 347infra-red 40, 4651, 20914ultra-violet 208, 210, 212, 214X- 208, 210, 212, 214, 312

radioactive dating 347, 352radioactive decay 3435, 352radioactivity 33852

di lid ( di i t ) 343 345 6


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RAM 314ratemeter 339ray, cathode 309

light 171, 176reaction time 83, 132

reactor, nuclear 3489real image 174, 195, 198rectification 31617red-shift 158, 373reed relay (switch) 320reflection, law of 168, 177

of sound 226, 2289total internal 18790, 192

refraction 168, 1847, 207, 239refractive index 1857refrigerator 56

relay, electromagnetic 289, 3201reliability of evidence 7, 359, 361renewable energy 14, 1036residual current circuit-breaker (RCCB)

272resistance 249, 2537, 259

measurement of 255, 259resistors 2557

in parallel 257, 261in series 256, 261

resonance 231resultant force 867, 89, 130reverberation 234revision 3825rheostat 255right-hand rule, Flemings 296ring main circuit 265, 26870ripple tank 1679road safety 69, 83, 138rocket engine 85, 138, 160rocks, dating 347, 352

Rutherford, Lord 342, 372, 377

S

safety belts 69, 83, 138Sankey diagram 1024, 116satellites 48, 153, 1545, 211, 223scalars 86scanning 211, 229, 312, 346, 357

seismic waves 1467, 373semi-conductor 316series circuits 250, 256, 261SETI, search for life 159shadows 172Snells Law 185solar cell 14, 103, 105, 115solar heating 14, 48, 50, 156solar system 1501 152

sound, frequency 225, 228, 2301loudness of 232, 234pitch 232quality of 233reflection of 2267, 2289

refraction of 239speed of 225, 227, 228sound waves 169, 225space travel 1601spark counter 339specific heat capacity 378specific latent heat, of fusion 534

of vaporisation 556spectacles 174, 196, 2023spectrum, electromagnetic 207215

visible 2067

speed 122of light 171, 185, 208of sound 227

speedtime graphs 89, 1235, 135sports 1345spring balance 667stability 935standard atmospheric pressure 80star 152, 1567static electricity 2417

steam engine 1001stopping distance 83strain (elastic) energy 10, 98, 108stroboscope 135Sun 70, 148, 152, 1567, 173Sun protection factor (SPF) 214supernova 157switch, two-way 265synthesizer 233

T

tape recorder 283, 307telecommunications 192, 218, 314telephone 216, 218, 289, 314telescopes 215television 169, 183, 209, 211, 221,

307, 30911temperature 267terminal velocity 89, 128

thermal energy 10, 26, 357, 98thermionic emission 308thermistor 218, 259, 319, 323, 329thermographs 50, 211, 21213thermometers 267, 218, 254, 319thermos flask 49thermostat, electric 23thinking distance 83tides 15 149

transformer 3013transistor 3225transmutation of elements 345transverse waves 146, 166, 171truth tables 3269

Uultrasound (ultrasonic) 226, 2289ultra-violet rays 208, 210, 212, 214umbra 1723universe, expanding 158, 373upthrust 87U-values 43

Vvacuum flask 49validity of evidence 7, 359valve, diode 308variables 7, 3604Van de Graaff generator 244vapour, water 56vectors 86velocity 122

of electromagnetic waves 208of light 171, 185, 208of sound 227

velocitytime graphs 89, 1235, 135vibrations 224volt 252, 261voltage divider 258, 318, 323, 329voltameter 273voltmeter 252volume, measurement of 75

Wwatt 110, 266wavelength 167

of electromagnetic waves 2089of light 207, 208, 210of sound 225

waves 1669, 20711, 225, 311weight 65, 67, 97, 131

weightlessness 68, 153, 160wheel and axle 118winds 14, 45, 103, 106wind turbine 14, 103, 106work 97, 99, 110

X


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Acknowledgement is also made to the following Examining Groups for permission to reprint questions from theirexamination papers. The questions are not necessarily from examinations for the current specification but are believed tobe relevant. The Examining Groups do not take responsibility for the answers provided.

AQA Assessment and Qualifications Alliance NIS Northern Ireland Schools Examinations CouncilEdex Edexcel Foundation WAEC West African Examinations CouncilOCR Oxford, Cambridge and RSA Examinations WJEC Welsh Joint Education CommitteeCam IGCSE University of Cambridge Local Examinations Syndicate (Cambridge IGCSE Physics Paper 6 Nov 06 Q2;

Nov 08 Q2)Edex IGCSE Edexcel IGCSE Examinations

Websites: www.physicsforyou.co.uk and www.physics4u.co.ukFrom these you can download exactly which pages in this book you need to study for your particular examination course.

Other books by Keith Johnson

Advanced Physics for Youwith Simmone Hewett, Sue Holt, and John MillerThis is written in the same friendly style as the GCSE

book, and covers the core of AS and A-level Physics,with over 200 worked examples.

Timetabling: A Timetablers CookBookThis book is a complete and practical guide for thosestaff responsible for timetabling in schools.

Spotlight Science 7, 8 and 9with Sue Adamson, Gareth Williams, Lawrie RyanThis is a flexible and accessible science course for

KS3, for students at all attainment levels.The Teachers Support Packs contain an enormousamount of valuable support material to supportdifferentiation in your teaching and learning.There are 2 versions: the original Spiral version andthe newer Framework version.

Photograph acknowledgements

Thanks to Chris and Rachel Johnson for checking the answers section.

AEA Te chnology: 346T , 350; Air Picture s: 169; Alex Se gre/Alamy: 182TL;Bettmann/Corbis: 377B; Blind Mobility Research Unit Nottingham: 228B; Bosch: 293;BoxMag Rapid: 288; British Aerospace: 51BR, 189B; British Rail Research: 22; BursteinCollection/Corbis: 371T; Photoshot/Bruce Coleman: 213TL; Camera Press: 376B; Castle

Associates: 234; Colorsport: 95TL, 108B, 134R, 135T, 135BR, 137; Corbis: 64BR Eddy

Lemaistre/Photo & Co, 138T Parrot Pascal, 215T, Jonathan Blair, 356B Lester Lefkowitz;Corel (NT): 6 C418, 42L C127, 106 C94, 114T C62, 122 C494, 208C C285; Digital Vision(NT): 4B, 150, 173, DV9, 82 DV13, 109 Karl Ammann DVAA, 128T DVXA, 149 DV6;Elcomer Instruments: 284; Fischer Scientific: 255; Ford Motor Company Ltd: 89; FormatPhotography: 389BL Brenda Prince, 389TL Maggie Murray; FLPA/Nigel Catlin: 361;GEC: 300; Getty Images: 64TR, 70, 95BR, 108T, 125, 128B, 130, 135BL; 291 John Stanton;iStock: 13, 42R, 47L, 71, 79, 114B, 116, 120, 138B, 182TC, 199C, 199B, 199A, 209D, 228T,240ML, 240BL, 240T, 252T, 260, 297, 306B, 309, 314, 315T; Joel Finler Collection: 201;John Bailey: 217T; Keith Johnson: 12, 64bl, 172, 174, 180, 188, 196, 199D, 199E, 220, 338T;Last Resort Picture Library: 83B; Leyland DAF: 97; London Buses: 95BL; London FireBrigade: 213TR; Martyn Chillmaid: 49, 86, 105, 182TR, 184, 186, 204, 203, 209A, 213BC,213BR, 229B, 232, 245, 250L, 250R, 252BL, 252BR, 275, 283, 302, 319T, 319B, 325, 327,331, 339, 344; Mary Evans Picture Library: 47BR, 95TR; 373BL Alamy; Barnabys PictureLibrary; MEMTEK: 231; NASA: 152, 153, 154, 158, 161T, 161BL, 161BR, 215B; NationalGallery London: 212 UML, 212 UMR; National Power: 15B; National Remote Sensing

Centre: 157T, 157B; Nokia: 216; OMRON: 27B; Ontario Science Centre: 244; PhotoDisc(NT): 200 PD40, 208A PD54, 208B PD18, 208E PD2, 209B PD22, 389TR PD72;Photolibrary: 146B; Racall: 311B; Ripleys Believe It or Not!: 312B; Robert HardingPicture Library: 45, 47TR; Rolls Royce: 389BC; Royal Astronomical Society: 151; RSComponents: 258; Sally & Richard Greenhill: 210B; Science and Society Picture Library:338B, 345; Science Photolibrary: 4t Dr Mitsuo Ohtsuki, 14T, 311T, 312TL, 371B, 374BL,375B, 376TR SPL, 14B, 50T, 103B, 115T Martin Bond, 27T Chris Priest & Mark Clarke,46L, 51BL, 182B, 212B, 217B, 240MR, 347T, 250B Cordelia Molloy, 46R Martyn F

Chillmaid, 50BL Dr Ray Clarke & Mervyn Goff, 51TR Dr Ray Clark, 64TL Alex Bartel,104T Kaj R. Svensson, 103T Tony Wood, 115M Peter Menzel, 127 Renee Lynn, 134L JerryWachter, 156, 159T, 160, 213BL, 352T NASA, 159B Robin Scagell, 155T David Ducros,155BL, 155BR, 146T NRSC Ltd, 166 Martin Dohrn, 173B George East, 182TL FrancoiseSauze, 189T Edelmann, 192 Steve Horrell, 193 Rosenfeld Images Ltd, 206 Simon Fraser,

207 Fred Burrell, 210T Martin Dohrn, 210M Phillipe Plailly, 211T Dr R. Clark & M.R.Goff, 211B Agema Infrared Systems, 212TL Erich Schrempp, 212TC Phil Jude, 212lML,212lMR, 267, 268R, 268C, 268L, 270, 374T, 375TL, 376TL Sheila Terry, 229T Saturn Stills,229UM Cnri, 229LM Alexander Tsiaras, 306T Dr Jeremy Burgess, 312TRStammers/Thompson, 346BL 346BR Elscint, 347B Gianni Tortoli, 348T Hank Morgan,356T David Parker, 356M James Prince, 357T Geof Tompkinson, 357B Hank Morgan, 358Samuel Ashfield, 372T Adam Hart-Davis, 372B National Library Of Medicine, 374MEmilio Segre Visual Archives/American Institute Of Physics, 374BR Sam Ogden, 375TRJean-Loup Charmet, 377TR Physics Today Collection/American Institute Of Physics,389BL James King-Holmes, 389ML Volker Steger, 389 BR Physics Department/ImperialCollege London, 389MC Mauro Fermariello, 389MR Maximilian Stock Ltd; ScottishPower: 15T; Shell: 74; Spectrum Colour Library: 53; Stone/ Getty Images: 104B; The PrintCollector/Alamy: 377TL; Time & Life Pictures/Getty Images: 373BR; Topfoto.co.uk: 83T,115B Rachel Epstein; Transport Research Laboratory: 69T USGS: 373T; Volvo: 69B;Yamaha: 233; ZEFA: 135M, 212TR.

Every effort has been made to trace and contact all copyright holders, but if any have beenoverlooked, the publisher will be pleased to make the necessary arrangements at the firstopportunity.

Picture research by [email protected] Sue Sharp

Illustrations by IFA Design Ltd, Tony Wilkins Illustration, Jordan Publishing Design, JaneCope and Ann Johnson


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