PEARSON BACCALAUREATE HIGHER LEVEL Physics · HIGHER LEVEL HIGHER LEVEL Supporting every learner across the IB continuum PEARSON BACCALAUREATE CHRIS HAMPER Physics 2nd Edition A01_IBPH_SB_IBGLB_9021_PRE.indd

HIGHER LE VEL

HIGHER LEVEL

Supporting every learner across the IB continuum

P E A R SO N B ACC A L AU R E AT E

CHRIS HAMPER

Physics 2nd Edition

A01_IBPH_SB_IBGLB_9021_PRE.indd 1 22/09/2014 13:23

Published by Pearson Education Limited, Edinburgh Gate, Harlow, Essex, CM20 2JE.

www.pearsonglobalschools.com

Text © Pearson Education Limited 2014

Edited by Gwynneth DrabbleProofread by Fern WatsonDesigned by Astwood DesignTypeset by Ken Vail Graphic DesignOriginal illustrations © Pearson Education 2014 Illustrated by Tech-Set Ltd and Ken Vail Graphic DesignCover design by Pearson Education Limited

The right of Chris Hamper to be identified as author of this work has been asserted by him in accordance with the Copyright, Designs and Patents Act 1988.

First published 2014

18 17 16 15 14IMP 10 9 8 7 6 5 4 3 2

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ISBN 978 1 447 95902 1 eBook only ISBN 978 1 447 95903 8

Copyright noticeAll rights reserved. No part of this publication may be reproduced in any form or by any means (including photocopying or storing it in any medium by electronic means and whether or not transiently or incidentally to some other use of this publication) without the written permission of the copyright owner, except in accordance with the provisions of the Copyright, Designs and Patents Act 1988 or under the terms of a licence issued by the Copyright Licensing Agency, Saffron House, 6–10 Kirby Street, London EC1N 8TS (www.cla.co.uk). Applications for the copyright owner’s written permission should be addressed to the publisher.

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Acknowledgements I would like to thank my family for supporting me through the ups and downs of the writing process. The physics students of UWCRCN for unknowingly testing my ideas, Mitch Campbell for help with astrophysics, my dog Ben for insisting that I take some fresh air breaks and Per for making me go rock climbing when I thought I didn’t have time.

The author of this book has received financial support from the Norwegian Non-fiction Literature Fund.

The author and publisher would like to thank the following individuals and organisations for permission to reproduce photographs:

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Alamy Images: Aerial Archives 208c, Bill Grant 419tr, Julie Edwards 130c, Noam Armonn 150bl; Chris Hamper: 11cr, 12tc, 38bl, 445c; Corbis: Bodo Marks / dpa 161cl, Christophe Boisvieux 34c, George Steinmetz 344bl, Martial Trezzini / epa 9t, Ocean 288tc, Pierre Jacques 417bl, Richard Du Toit / Minden Pictures 148c, Stocktrek Images 530c, 549tl; Fotolia.com: EcoPim-studio 307tr, gekaskr 241c, Gudellaphoto 430bc, nikkytok 476c, TEK IMAGE 334bl; Getty Images: DAJ 436t, Hulton Archive 51bc, Image Source 168bl, Pegasus / Visuals Unlimited, Inc. 68c, Rachel Husband 428tc, Trout55 172bc; Glow Images: 65c, 70bc, 92c; Ole Karsten Birkeland: 72tl; PASCO scientific (www.pasco.com): 44cl, 133br, 449tr, 489t; Science Photo Library Ltd: A. Bolton / H-s Cfa / Slacs / Nasa / Esa / Stsci 404cl, 143bc, 521br, Alex Bartel 173t, Andrew Lambert Photography 175tr, 175cr, 242tr, 288cl, 466c, 469tr, Antoine Rosset 516cl, B. Mcnamara (university Of Waterloo) / Nasa / Esa / Stsci 576tr, Babak Tafreshi, Twan 533cr, 535c, Bernhard Edmaier 345bl, Carlos Munoz Yague / Look At Sciences 229cr,

Charles D. Winters 96tc, 120bc, David Nunuk 124c, David Parker 188tr, 504bc, Dept. Of Physics, Imperial College 281tl, Dr Najeeb Layyous 519br, Dr. Arthur Tucker 106tl, Drs A. Yazdani & D.j. Hornbaker 294c, Edward Kinsman 49tl, Erich Schrempp 187tr, European Southern Observatory 563tr, Giphotostock 31bc, 288bl, Goronwy Tudor Jones, University Of Birmingham 301bc, Gustoimages 515br, John Beatty 107bl, John Heseltine 197cr, John Sanford 538bc, K. H. Kjeldsen 576br, Kaj R. Svensson 129br, Lawrence Berkeley Laboratory 246cr, 293tr, Lawrence Livermore National Laboratory 276c, Leonard Lessin 320cl, Mark Clarke 131c, Mark Sykes 105tc, 199cr, Mark Williamson 461tc, Martin Bond 163t, 350cl, Martin Rietze / Westend61 332c, Maximilien Brice, Cern 366c, Mehau Kulyk 293tc, Nasa 401b, 504tl, Nasa / Bill Ingalls 562tl, Nasa / Esa / Stsci / J.hester & P.scowen, Asu 531bc, Nasa / Esa / Stsci / W.colley & E.turner, Princeton 555bc, Nasa / Jpl-caltech 552cl, Nasa / Wmap Science Team 565tc, Pasieka 416c, Pasquale Sorrentino 179tl, Peter Muller 258tl, Philippe Plailly 60bl, Photostock-israel 336br, Physics Dept., Imperial College 542t, Ria Novosti 340cl, Ronald Royer 535tr, Royal Astronomical Society 404tl, 503bc, Seymour 311tr, Sheila Terry 343cr, 372tr, Simon Fraser / Dept. Of Neurology, Newcastle General Hospital 521bl, Ted Kinsman 100bc, Tek Image 2c

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Text Quote on page 3 from http://www.bipm.org/en/si/si_brochure/ Bureau International des Poids et Mesures, organisation intergouvernementale de la Convention du Mètre, The International System of Units (SI), Bureau International des Poids et Mesures, March 2006. Web: 21 May 2012, reproduced with permission of the BIPM, which retains full internationally protected copyright; Quote on page 351 from the IPCC website: http://www.ipcc.ch/organization/organization.shtml#.Uc6QPJw8lXY Intergovernmental panel on climate change (IPCC); Quote on page 999 from The Ultimate Quotable Einstein (Alice Calaprice), with permission: The Albert Einstein Archives, The Hebrew University of Jerusalem; Quote on page 1004 from http://www.aphorismsgalore.com/aphorists/Albert%20Einstein, with permission: The Albert Einstein Archives, The Hebrew University of Jerusalem; Quote on page 1007 from Carl Sagan http://www.carlsagan.com/ with permission.

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The Understandings, Applications and Skills, Guidance, Essential ideas, past exam questions, corresponding mark schemes provided on the eBook, and assessment criteria have been reproduced from IB documents and past examination papers. Our thanks go to the International Baccalaureate for permission to reproduce its intellectual copyright.

This material has been developed independently by the publisher and the content is in no way connected with or endorsed by the International Baccalaureate (IB).

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Contents Introduction v

1 Measurements and uncertainties 21.1 Measurements in physics 3

1.2 Uncertainties and errors 8

1.3 Vectors and scalars 24

2 Mechanics 342.1 Motion 35

2.2 Forces 52

2.3 Momentum and impulse 61

2.4 Work, energy, and power 73

3 Thermal physics 923.1 Thermal concepts 93

3.2 Modelling a gas 112

4 Circular motion and gravitation 1244.1 Circular motion 125

4.2 Gravitational fi eld and orbits 132

5 Oscillations and waves 1485.1 Oscillations 150

5.2 Waves and wave behaviour 161

5.3 Two-dimensional waves (water waves) 172

5.4 Sound waves 177

5.5 Light waves 183

6 Electricity and magnetism 2086.1 Electric fi elds 210

6.2 Electric current 218

6.3 Electric circuits 222

6.4 Magnetic effects of electric currents 241

6.5 Electromagnetic induction 247

6.6 Power generation and transmission 252

6.7 Capacitance 260

iii


7 Atomic, nuclear, and particle physics 2767.1 Discrete energy and the interaction of matter with radiation 277

7.2 Properties of the nucleus and radioactivity 294

7.3 The structure of matter 313

8 Energy production 3328.1 Energy production 333

8.2 Global thermal energy transfer 351

9 Option A: Relativity 3669.1 The beginnings of relativity 367

9.2 Lorentz transformations 375

9.3 Space–time diagrams 388

9.4 Relativistic mechanics 394

9.5 General relativity 400

10 Option B: Engineering physics 41610.1 Rigid bodies and rotational dynamics 418

10.2 Thermodynamics 438

10.3 Fluids and their dynamics 450

10.4 Forced vibration and resonance 465

11 Option C: Imaging 47611.1 Introduction to imaging 477

11.2 Imaging instrumentation 495

11.3 Fibre optics 506

11.4 Medical imaging 510

12 Option D: Astrophysics 53012.1 Stellar quantities 532

12.2 Stellar characteristics 540

12.3 Stellar evolution 548

12.4 Cosmology 554

Theory of Knowledge 570

Internal assessment 580

Extended essay 597

iv

Contents


IntroductionAuthor’s introduction to the second editionWelcome to your study of IB Higher Level physics! This second edition has been completely rewritten to match the specifi cations of the new IB physics curriculum, and gives thorough coverage of the entire

course content. While there is much new and updated material, we have kept and refi ned the features that made the fi rst edition so successful.

ContentThe book covers the three parts of the IB syllabus: the core, the AHL (additional higher level) material and the options, of which you will study one. The AHL material is integrated with the core material and the

sequence in which the sub-topics are covered is given in the Contents list. Each chapter starts with a list of the Essential ideas from the IB physics guide, which summarize the focus of each sub-topic.

Essential ideas3.1 Thermal concepts

Thermal physics deftly demonstrates the links between the macroscopic measurements essential to many scientifi c models with the microscopic properties that underlie these models.

This is followed by an introduction, which gives the context of the topic and how it relates to your previous knowledge. The relevant sections from the IB physics guide for each sub-topic are then given as boxes showing Understanding, applications and skills,

with notes for Guidance shown in italics where they help interpret the syllabus. The headings above the Understandings, applications and skills boxes refer to the numbering within the IB guide.

1.1 Measurements in physics

Understandings, applications, and skills:Fundamental and derived SI units

● Using SI units in the correct format for all required measurements, fi nal answers to calculations and presentation of raw and processed data.

GuidanceSI unit usage and information can be found at the website of Bureau International des Poids et Mesures. Students will not need to know the defi nition of SI units except where explicitly stated in the relevant topics. Candela is not a required SI unit for this course.

Scientifi c notation and metric multipliers ● Using scientifi c notation and metric multipliers.

Signifi cant fi guresOrders of magnitude

● Quoting and comparing ratios, values, and approximations to the nearest order of magnitude.Estimation

● Estimating quantities to an appropriate number of signifi cant fi gures.

The text covers the course content using plain language, with all scientifi c terms explained and shown in bold as they are fi rst introduced. We have

been careful also to apply the same terminology you will see in IB examinations in all worked examples and questions.

v


The nature of scienceThroughout the course you are encouraged to think about the nature of scientifi c knowledge and the scientifi c process as it applies to physics. Examples are given of the evolution of physical theories as new information is gained, the use of models to conceptualize our understanding, and the ways in which experimental work is enhanced by modern technologies. Ethical considerations, environmental impacts, the importance of objectivity,

and the responsibilities regarding scientists’ code of conduct are also considered here. The emphasis is not on learning any of these examples, but rather appreciating the broader conceptual themes in context. We have included at least one example in each sub-section, and hope you will come up with your own as you keep these ideas at the surface of your learning.

Key to information boxesA popular feature of the book is the different coloured boxes interspersed through each chapter.

These are used to enhance your learning as explained below.

Nature of science

This is an overarching theme in the course to promote concept-based learning. Through the book you should recognize some similar themes emerging across different topics. We hope they help you to develop your own skills in scientifi c literacy.

International-mindedness

The impact of the study of physics is global, and includes environmental, political and socio-economic considerations. Examples of this are given here to help you to see the importance of physics in an international context.

Utilization

Applications of the topic through everyday examples are described here, as well as brief descriptions of related physical industries. This helps you to see the relevance and context of what you are learning.

Newton’s three laws of motion are a set of statements, based on observation and experiment, that can be used to predict the motion of a point object from the forces acting on it. Einstein showed that the laws do not apply when speeds approach the speed of light. However, we still use them to predict outcomes at the lower velocities achieved by objects travelling in the lab.

In cold countries houses are insulated to prevent heat from escaping. Are houses in hot countries insulated to stop heat entering?

Although the fi rst ever engine was probably a steam turbine, cylinders of expanding gas are the basis of most engines.

vi

Introduction


Interesting fact

These give background information that will add to your wider knowledge of the topic and make links with other topics and subjects. Aspects such as historic notes on the life of scientists and origins of names are included here.

Laboratory work

These indicate links to ideas for lab work and experiments that will support your learning in the course, and help you prepare for the Internal Assessment. Some specifi c experimental work is compulsory, and further details of this are in the eBook.

TOK

These stimulate thought and consideration of knowledge issues as they arise in context. Each box contains open questions to help trigger critical thinking and discussion.

Key fact

These key facts are drawn out of the main text and highlighted in bold. This will help you to identify the core learning points within each section. They also act as a quick summary for review.

Hints for success

These give hints on how to approach questions, and suggest approaches that examiners like to see. They also identify common pitfalls in understanding, and omissions made in answering questions.

Specifi c heat capacity of a metal

A metal sample is fi rst heated to a known temperature. The most convenient way of doing this is to place it in boiling water for a few minutes; after this time it will be at 100 °C. The hot metal is then quickly moved to an insulated cup containing a known mass of cold water. The hot metal will cause the temperature of the cold water to rise; the rise in temperature is measured with a thermometer. Some example temperatures and masses are given in Figure 3.34.

We perceive how hot or cold something is with our senses but to quantify this we need a measurement.

Solid ➞ liquid

Specifi c latent heat of fusion

Liquid ➞ gas

Specifi c latent heat of vaporization

People sweat to increase the rate at which they lose heat. When you get hot, sweat comes out of your skin onto the surface of your body. When the sweat evaporates, it cools you down. In a sauna there is so much water vapour in the air that the sweat doesn’t evaporate.

There are two versions of the equation for centripetal force

Speed version:

F = mv²r

Angular speed version:

F = mω ²r

vii


Challenge yourselfThese boxes contain open questions that encourage you to think about the topic in more depth, or to make detailed connections with other topics. They are designed to be challenging and to make you think.

Towards the end of the book, there are three appendix chapters: Theory of Knowledge as it relates to physics, and advice on the Extended Essay and Internal Assessment.

eBookIn the eBook you will fi nd the following:

● Interactive glossary of scientifi c words used in the course● Answers and worked solutions to all exercises in the book● Summary and labs worksheets● Interactive quizzes● Animations ● Videos

For more details about your eBook, see the following section.

QuestionsThere are three types of question in this book:

1. Worked example with solutionThese appear at intervals in the text and are used to illustrate the concepts covered. They are followed by

the solution, which shows the thinking and the steps used in solving the problem.

Worked example

Referring to Figure 4.21 if a body is moved from A to B what is the change in potential?

Solution

VA = 30 J kg–1

VB = 80 J kg–1

Change in potential = 80 – 30 = 50 J kg–1

CHALLENGE YOURSELF1 A car of mass 1000 kg is driving

around a circular track with radius 50 m. If the coefficient of friction between the tyres and road is 0.8, calculate the maximum speed of the car before it starts to slip. What would the maximum speed be if the track was banked at 45°?

viii

Introduction


2. ExercisesThese questions are found throughout the text. They allow you to apply your knowledge and test your understanding of what you have just been reading.

The answers to these are given on the eBook at the end of each chapter.

Exercises7 Calculate the mass of air in a room of length 5 m, width 10 m, and height 3 m.

8 Calculate the mass of a gold bar of length 30 cm, width 15 cm, and height 10 cm.

9 Calculate the average density of the Earth.

3. Practice questionsThese questions are found at the end of each chapter. They are mostly taken from previous years’ IB examination papers. The mark-schemes used by

examiners when marking these questions are given in the eBook, at the end of each chapter.

Practice questions1. This question is about energy sources.

(a) Fossil fuels are being produced continuously on Earth and yet they are classed as being non-renewable. Outline why fossil fuels are classed as non-renewable. (2)

(b) Some energy consultants suggest that the solution to the problem of carbon dioxide pollution is to use nuclear energy for the generation of electrical energy. Identify two disadvantages of the use of nuclear fi ssion when compared to the burning of fossil fuels for the generation of electrical energy. (2)

(Total 4 marks)

Worked solutionsFull worked solutions to all exercises and practice questions can be found in the eBook, as well as regular answers.

Hotlinks boxes can be found throughout the book, indicating that there are weblinks available for further study. To access these links go to www.pearsonhotlinks.com and enter the ISBN or title of this book. Here you can fi nd animations, simulations, movie clips and related background material, which can help to deepen your interest and understanding of the topic.

I hope you enjoy your study of IB physics.

Chris Hamper

ix


This is an approximation of what your eBook will look like and not an exact reproduction

ionization

current

A

By detecting this � ow of charge we can count individual particles. However, since all of the particles are ionizing we can’t tell which type of radiation it is. To do this we can use their different penetrating powers: most alpha particles, being the biggest, can be stopped by a sheet of paper; beta particles can pass through paper but are stopped by a thin sheet of aluminium; gamma rays, which are the same as high energy X-rays, are the most penetrating and will even pass through lead. For the same reason, the different radiations have varying ranges in air: alpha particles only travel a few cm, beta particles travel about 10 times further, gamma radiation travels furthest but interacts slightly differently, resulting in an inverse square reduction in intensity with increasing distance.

paper aluminium lead

–

α

β

γ

An alternative way of detecting radioactive particles is using a cloud chamber. This contains a vapour which turns into droplets of liquid when an ionizing particle passes through. This results in a visible line showing the path of the particle, rather like the vapour trail behind an airplane. A bubble chamber is similar but the trail is a line of bubbles.

Figure 7.33 An ionization chamber.

Figure 7.34 Absorption of radiation.

A bubble chamber photograph from the CERN accelerator. There is a magnetic fi eld directed out of the chamber causing positive particles to spiral clockwise.

example, the binding energy per nucleon of 54Fe is 471.554 = 8.7 MeV/nucleon. Figure 7.32

shows the BE/nucleon plotted against nucleon number for a variety of nuclei.

From Figure 7.32 we can see that some nuclei are more stable than others: iron and nickel are in the middle so they are the most stable nuclei. If small nuclei join to make larger ones the binding energy per nucleon increases resulting in a release of energy, but to make nuclei bigger than iron, energy would have to be put in. This tells us something about how the different elements found on Earth must have been formed. Small nuclei are formed in the centre of stars as the matter gets pulled together by gravity releasing energy in the form of the light we see. When big nuclei form, energy is absorbed – this happens towards the end of a star’s life. There are more details about this in Chapter 12.

Exercises21 Find uranium in Table 7.3.

(a) How many protons and neutrons does uranium have?(b) Calculate the total mass, in unified mass units, of the protons and neutrons that make uranium.(c) Calculate the difference between the mass of uranium and its constituents (the mass defect).(d) What is the binding energy of uranium in MeV?(e) What is the BE per nucleon of uranium?

22 Enter the data from the table into a spreadsheet. Add formulae to the spreadsheet to calculate the binding energy per nucleon for all the nuclei and plot a graph of BE/nucleon against nucleon number.

Radioactive decayTo explain why a ball rolls down a hill we can say that it is moving to a position of lower potential energy. In the same way, the combination of protons and neutrons in a nucleus will change if it results in an increased binding energy. This sounds like it is the wrong way round but remember, binding energy is the energy released when a nucleus is formed so if a nucleus changes to one of higher binding energy then energy must be released. There are three main ways that a nucleus can change:

• alpha emission. Alpha particles are helium nuclei. Emission of a helium nucleus results in a smaller nucleus so according to the binding energy per nucleon curve, this would only be possible in large nuclei.

• changing a neutron to a proton. This results in the emission of an electron (beta minus).

• changing a proton to a neutron. This results in the emission of a positive electron (positron) (beta plus). This is quite rare.

Notice that all three changes result in the emission of a particle that takes energy away from the nucleus. Energy can also be lost by the emission of high energy electromagnetic radiation (gamma). The amount of energy associated with nuclear reactions is in the order of MeV so these particles are ejected at high speed. Ionizing an atom requires a few eV so one of these particles can ionize millions of atoms as they travel through the air. This makes them harmful, but also easy to detect.

Detecting radiationA Geiger–Muller, or GM, tube is a type of ionization chamber. It contains a low pressure gas which, when ionized by a passing particle, allows a current to � ow between two electrodes as in Figure 7.33.

Figure 7.32 is a very important graph which is used to explain almost every aspect of nuclear reactions from the energy production in stars to problems with nuclear waste.

Remember: 1u is equivalent to 931.5 MeV.

CHALLENGE YOURSELF1 Estimate the amount of

energy in joules required to break 3 g of copper (63Cu) into its constituent nucleons.

301300

Atomic, nuclear, and particle physics07

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(b) Calculate the total mass, in unified mass units, of the protons and neutrons that make uranium.Calculate the difference between the mass of uranium and its constituents (the mass defect).


Radioactive decayRadioactive decay

PRIVATE NOTE

Do exercises 21, 22, and quiz for homework.Note

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x


ionization

current

A

By detecting this � ow of charge we can count individual particles. However, since all of the particles are ionizing we can’t tell which type of radiation it is. To do this we can use their different penetrating powers: most alpha particles, being the biggest, can be stopped by a sheet of paper; beta particles can pass through paper but are stopped by a thin sheet of aluminium; gamma rays, which are the same as high energy X-rays, are the most penetrating and will even pass through lead. For the same reason, the different radiations have varying ranges in air: alpha particles only travel a few cm, beta particles travel about 10 times further, gamma radiation travels furthest but interacts slightly differently, resulting in an inverse square reduction in intensity with increasing distance.

paper aluminium lead

–

α

β

γ

An alternative way of detecting radioactive particles is using a cloud chamber. This contains a vapour which turns into droplets of liquid when an ionizing particle passes through. This results in a visible line showing the path of the particle, rather like the vapour trail behind an airplane. A bubble chamber is similar but the trail is a line of bubbles.

Figure 7.33 An ionization chamber.

Figure 7.34 Absorption of radiation.

A bubble chamber photograph from the CERN accelerator. There is a magnetic fi eld directed out of the chamber causing positive particles to spiral clockwise.

example, the binding energy per nucleon of 54Fe is 471.554 = 8.7 MeV/nucleon. Figure 7.32

shows the BE/nucleon plotted against nucleon number for a variety of nuclei.

From Figure 7.32 we can see that some nuclei are more stable than others: iron and nickel are in the middle so they are the most stable nuclei. If small nuclei join to make larger ones the binding energy per nucleon increases resulting in a release of energy, but to make nuclei bigger than iron, energy would have to be put in. This tells us something about how the different elements found on Earth must have been formed. Small nuclei are formed in the centre of stars as the matter gets pulled together by gravity releasing energy in the form of the light we see. When big nuclei form, energy is absorbed – this happens towards the end of a star’s life. There are more details about this in Chapter 12.

Exercises21 Find uranium in Table 7.3.

(a) How many protons and neutrons does uranium have?(b) Calculate the total mass, in unified mass units, of the protons and neutrons that make uranium.(c) Calculate the difference between the mass of uranium and its constituents (the mass defect).(d) What is the binding energy of uranium in MeV?(e) What is the BE per nucleon of uranium?


Radioactive decayTo explain why a ball rolls down a hill we can say that it is moving to a position of lower potential energy. In the same way, the combination of protons and neutrons in a nucleus will change if it results in an increased binding energy. This sounds like it is the wrong way round but remember, binding energy is the energy released when a nucleus is formed so if a nucleus changes to one of higher binding energy then energy must be released. There are three main ways that a nucleus can change:

• alpha emission. Alpha particles are helium nuclei. Emission of a helium nucleus results in a smaller nucleus so according to the binding energy per nucleon curve, this would only be possible in large nuclei.

• changing a neutron to a proton. This results in the emission of an electron (beta minus).

• changing a proton to a neutron. This results in the emission of a positive electron (positron) (beta plus). This is quite rare.

Notice that all three changes result in the emission of a particle that takes energy away from the nucleus. Energy can also be lost by the emission of high energy electromagnetic radiation (gamma). The amount of energy associated with nuclear reactions is in the order of MeV so these particles are ejected at high speed. Ionizing an atom requires a few eV so one of these particles can ionize millions of atoms as they travel through the air. This makes them harmful, but also easy to detect.

Detecting radiationA Geiger–Muller, or GM, tube is a type of ionization chamber. It contains a low pressure gas which, when ionized by a passing particle, allows a current to � ow between two electrodes as in Figure 7.33.

Figure 7.32 is a very important graph which is used to explain almost every aspect of nuclear reactions from the energy production in stars to problems with nuclear waste.

Remember: 1u is equivalent to 931.5 MeV.

CHALLENGE YOURSELF1 Estimate the amount of

energy in joules required to break 3 g of copper (63Cu) into its constituent nucleons.

301300

Atomic, nuclear, and particle physics07

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See the defi nitions of key terms in the glossary

Switch to whiteboard view

Animation

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Quiz

Select the icon to take an interactive quiz to test your knowledge

Answers

Select the icon at the end of the chapter to view answers to exercises in this chapter

Worked solutions

Select the icon at the end of the chapter to view worked solutions to exercises in this chapter

xi


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PEARSON BACCALAUREATE HIGHER LEVEL Physics · HIGHER LEVEL HIGHER LEVEL Supporting every learner across the IB continuum PEARSON BACCALAUREATE CHRIS HAMPER Physics 2nd Edition A01_IBPH_SB_IBGLB_9021_PRE.indd