SGK LÝ 10 Nam Phi (English)

FHSST Authors The Free High School Science Texts: Textbooks for High School Students Studying the Sciences Physical Science Grade 10 Version 0.5 September 9, 2010 ii Copyright 2007 “Free High School Science Texts” Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front- Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled “GNU Free Documentation License”. STOP!!!! Did you notice the FREEDOMS we’ve granted you? Our copyright license is different! 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Thousands of hours went into making them and they are a gift to everyone in the education community. iii FHSST Core Team Mark Horner ; Samuel Halliday ; Sarah Blyth ; Rory Adams ; Spencer Wheaton FHSST Editors Jaynie Padayachee ; Joanne Boulle ; Diana Mulcahy ; Annette Nell ; Ren´e Toerien ; Donovan Whitfield FHSST Contributors Sarah Abel ; Dr. Rory Adams ; Andrea Africa ; Ben Anhalt ; Prashant Arora ; Raymond Barbour ; Richard Baxter ; Tara Beckerling ; Tim van Beek ; Jennifer de Beyer ; Dr. Sarah Blyth ; Sebastian Bodenstein ; Martin Bongers ; Stephan Brandt ; Craig Brown ; Graeme Broster ; Deanne de Bude ; Richard Case ; Fa n ny Cherblanc ; Dr. Christin e Chung ; Brett Cocks ; Andrew Craig ; Tim Crombie ; Dan Crytser ; Dr. Anne Dabrowski ; Laura Daniels ; Sean Dobbs ; Esmi Dreyer ; Matthew Duddy ; Fernando Durrell ; Dr. Dan Dwyer ; Frans van Eeden ; Alex Ellis ; Tom Ellis ; Giovanni Franzoni ; Ingrid von Glehn ; Tamara von Glehn ; Lindsay Glesener ; Kevin Godby ; Dr. Vanessa Godfrey ; Dr. Johan Gonzalez ; Hemant Gopal ; Dr. S te ph a ni e Gould ; Umeshree Govender ; Heather Gray ; Lynn Greeff ; Dr. Tom Gutierrez ; Brooke Haag ; Kate Hadley ; Dr. Sam Halliday ; Asheena Hanuman ; Dr Melanie Dymond Harper ; Dr. Nicholas Harrison ; Neil Hart ; Nicholas Hatcher ; Dr. William P. Heal ; Pierre van Heerden ; Dr. Fritha Hennessy ; Millie Hilgart ; Chris Holdsworth ; Dr. Benne Holwerda ; Dr. M ark Horner ; Mfandaidza Hove ; Robert Hovden ; Jennifer Hsieh ; Clare Johnson ; Luke Jordan ; Tana Joseph ; Dr. Fabian Jutz ; Dr. Lutz Kamp man n ; Paul Kim ; Dr. Jennifer Klay ; Lara Kruger ; Sihle Kubheka ; Andrew Kubik ; Dr. Jannie Leach ; Dr. Marco van Leeuwen ; Dr. Tom Leinster ; Dr. Anton Machacek ; Dr. Komal Maheshwari ; Kosma von Maltitz ; Bryony Martin ; Nicole Masureik ; John Mathew ; Dr. Will Matthews ; JoEllen McBride ; Nikolai Meures ; Riana Meyer ; Filippo Miatto ; Jenny Miller ; Abdul Mirza ; Mapholo Modi se ; Carla Moerdyk ; Asogan Moodaly ; Jothi Moodley ; David Myburgh ; Kamie Naidu ; Nolene Naidu ; Bridget Nash ; Tyrone Negus ; Thomas O’Donnell ; Dr. Markus Oldenburg ; Dr. Jaynie Padayachee ; Dave Pawson ; Nicolette Pekeur ; Sirika Pillay ; Jacques Plaut ; Andrea Prinsloo ; Joseph Raimondo ; Sa nya Rajani ; Prof. Sergey Rakityansky ; Alastair Ramlakan ; Dr. M at in a J. 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Should you have suggestions, find mistakes or be prepared to donate material for inclusion, please don’t hesitate to contact us. We intend to work with all who are willing to help make this a continuously evolving resource! www.fhsst.org iv Contents 1 Units 1 1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Unit Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2.1 SI Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2.2 The Other Systems of Units . . . . . . . . . . . . . . . . . . . . . . . . 2 1.3 Writing Units as Words or Symbols . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.4 Combinations of SI Base Units . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.5 Rounding, Scientific Notation and Significant Figures . . . . . . . . . . . . . . . 4 1.5.1 Rounding Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.5.2 Error Margins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.5.3 Scientific Notation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.5.4 Significant Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.6 Prefixes of Base Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.7 The Importance of Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 1.8 How to Change Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 1.8.1 Two other useful conversions . . . . . . . . . . . . . . . . . . . . . . . . 12 1.9 A sanity test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 1.10 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 1.11 End of Chapter Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 I Chemistry 15 2 Classification of Matter - Grade 10 17 2.1 Mixtures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.1.1 Heterogeneous mixtures . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.1.2 Homogeneous mixtures . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.1.3 Separating mixtures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2.2 Pure Substances: Elements and Compounds . . . . . . . . . . . . . . . . . . . . 21 2.2.1 Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 2.2.2 Compounds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 2.3 Giving names and formulae to substances . . . . . . . . . . . . . . . . . . . . . 22 2.4 Metals, Semi-metals and Non-metals . . . . . . . . . . . . . . . . . . . . . . . . 25 2.4.1 Metals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 v CONTENTS CONTENTS 2.4.2 Non-metals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 2.4.3 Semi-metals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 2.5 Electrical conductors, semi-conductors and insulators . . . . . . . . . . . . . . . 26 2.6 Thermal Conductors and Insulators . . . . . . . . . . . . . . . . . . . . . . . . . 27 2.7 Magnetic and Non-magnetic Materials . . . . . . . . . . . . . . . . . . . . . . . 29 2.8 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 3 What are the objects around us made of? - Grade 10 33 3.1 Introduction: The atom as the building block of matter . . . . . . . . . . . . . . 33 3.2 Molecules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 3.2.1 Representing molecules . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 3.3 Intramolecular and intermolecular forces . . . . . . . . . . . . . . . . . . . . . . 37 3.4 The Kinetic Theory of Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 3.5 The Properties of Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 3.6 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 4 The Atom - Grade 10 47 4.1 Models of the Atom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 4.1.1 The Plum Pudding Model . . . . . . . . . . . . . . . . . . . . . . . . . . 47 4.1.2 Rutherford’s model of the atom . . . . . . . . . . . . . . . . . . . . . . 48 4.1.3 The Bohr Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 4.2 How big is an atom? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 4.2.1 How heavy is an atom? . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 4.2.2 How big is an atom? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 4.3 Atomic structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 4.3.1 The Electron . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 4.3.2 The Nucleus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 4.4 Atomic number and atomic mass number . . . . . . . . . . . . . . . . . . . . . 52 4.5 Isotopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 4.5.1 What is an isotope? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 4.5.2 Relative atomic mass . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 4.6 Energy quantisation and electron configuration . . . . . . . . . . . . . . . . . . 59 4.6.1 The energy of electrons . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 4.6.2 Energy quantisation and line emission spe ct ra . . . . . . . . . . . . . . . 59 4.6.3 Electron configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 4.6.4 Core and valence electrons . . . . . . . . . . . . . . . . . . . . . . . . . 64 4.6.5 The importance of understanding electron configuration . . . . . . . . . 64 4.7 Ionisation Energy and the Periodic Table . . . . . . . . . . . . . . . . . . . . . . 66 4.7.1 Ions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 4.7.2 Ionisation Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 4.8 The Arrangement of Atoms in the Periodic Table . . . . . . . . . . . . . . . . . 68 4.8.1 Groups in the periodic table . . . . . . . . . . . . . . . . . . . . . . . . 68 4.8.2 Periods in the periodic table . . . . . . . . . . . . . . . . . . . . . . . . 70 4.9 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 vi CONTENTS CONTENTS 5 Physical and Chemical Change - Grade 10 75 5.1 Physical changes in matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 5.2 Chemical Changes in Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 5.2.1 Decomposition reactions . . . . . . . . . . . . . . . . . . . . . . . . . . 77 5.2.2 Synthesis reactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 5.3 Energy changes in chemical reactions . . . . . . . . . . . . . . . . . . . . . . . . 81 5.4 Conservation of atoms and mass in reactions . . . . . . . . . . . . . . . . . . . . 81 5.5 Law of constant composition . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 5.6 Volume relationships in gases . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 5.7 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 6 Representing Chemical Change - Gr ade 10 87 6.1 Chemical symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 6.2 Writing chemical formulae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 6.3 Balancing chemical equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 6.3.1 The law of conservation of mass . . . . . . . . . . . . . . . . . . . . . . 88 6.3.2 Steps to balance a chemical equation . . . . . . . . . . . . . . . . . . . 90 6.4 State symbols and other information . . . . . . . . . . . . . . . . . . . . . . . . 94 6.5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 7 The Water Cycle - Grade 10 99 7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 7.2 The importance of water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 7.3 The movement of water through the water cycle . . . . . . . . . . . . . . . . . . 100 7.4 The microscopic structure of water . . . . . . . . . . . . . . . . . . . . . . . . . 103 7.4.1 The polar nature of water . . . . . . . . . . . . . . . . . . . . . . . . . . 103 7.4.2 Hydrogen bonding in water molecules . . . . . . . . . . . . . . . . . . . 103 7.5 The unique properties of water . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 7.6 Water conservation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 7.7 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110 8 Global Cycle s: The Nitrogen Cycle - Grade 10 113 8.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 8.2 Nitrogen fixation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 8.3 Nitrification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 8.4 Denitrification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 8.5 Human Influences on the Nitrogen Cycle . . . . . . . . . . . . . . . . . . . . . . 116 8.6 The industrial fixation of nitrogen . . . . . . . . . . . . . . . . . . . . . . . . . 117 8.7 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119 9 The Hydrosphere - Grade 10 121 9.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 9.2 Interactions of the hydrosphere . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 vii CONTENTS CONTENTS 9.3 Exploring the Hydrosphere . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 9.4 The Importance of the Hydrosphere . . . . . . . . . . . . . . . . . . . . . . . . 123 9.5 Ions in aqueous solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 9.5.1 Dissociation in water . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 9.5.2 Ions and water hardness . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 9.5.3 The pH scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 9.5.4 Acid rain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 9.6 Electrolytes, ionisation and conductivity . . . . . . . . . . . . . . . . . . . . . . 130 9.6.1 Electrolytes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 9.6.2 Non-electrolytes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 9.6.3 Factors that affect the conductivity of water . . . . . . . . . . . . . . . . 131 9.7 Precipitation reactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 9.8 Testing for common anions in solution . . . . . . . . . . . . . . . . . . . . . . . 135 9.8.1 Test for a chloride . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 9.8.2 Test for a sulphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 9.8.3 Test for a carbona te . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 9.8.4 Test for bromides and iodides . . . . . . . . . . . . . . . . . . . . . . . . 136 9.9 Threats to the Hydrosphere . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 9.10 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 II Physics 141 10 Units 143 10.1 Introducti on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 10.2 Unit Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 10.2.1 SI Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 10.2.2 The Other Systems of Units . . . . . . . . . . . . . . . . . . . . . . . . 144 10.3 Writing Units as Words or Symbols . . . . . . . . . . . . . . . . . . . . . . . . . 144 10.4 Combinations of SI Base Units . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 10.5 Rounding, Scientific Notation and Significant Figures . . . . . . . . . . . . . . . 145 10.5.1 Rounding Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 10.5.2 Error Margins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 10.5.3 Scientific Notation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147 10.5.4 Significant Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147 10.6 Prefixes of Base Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148 10.7 The Importance of Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 10.8 How to Change Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150 10.8.1 Two other useful conversions . . . . . . . . . . . . . . . . . . . . . . . . 151 10.9 A sanity test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151 10.10Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 10.11End of Chapter Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 viii CONTENTS CONTENTS 11 Motion in One Dimensi on - Grade 10 155 11.1 Introducti on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155 11.2 Reference Point, Frame of Reference and Position . . . . . . . . . . . . . . . . . 155 11.2.1 Frames of Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155 11.2.2 Position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156 11.3 Displacement and Distance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 11.3.1 Interpreting Direction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 11.3.2 Differences between Distance and Displacement . . . . . . . . . . . . . . 159 11.4 Speed, Average Velocity and Instantaneous Velocity . . . . . . . . . . . . . . . . 160 11.4.1 Differences between Speed and Velocity . . . . . . . . . . . . . . . . . . 164 11.5 Acceleration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 11.6 Description of Motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169 11.6.1 Stationary Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169 11.6.2 Motion at Constant Velocity . . . . . . . . . . . . . . . . . . . . . . . . 170 11.6.3 Motion at Constant Acceleration . . . . . . . . . . . . . . . . . . . . . . 174 11.7 Summary of Graphs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176 11.8 Worked Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177 11.9 Equations of Motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183 11.9.1 Finding the Equations of Motion . . . . . . . . . . . . . . . . . . . . . . 183 11.10App li ca tion s in the Real-World . . . . . . . . . . . . . . . . . . . . . . . . . . . 188 11.11Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191 11.12End of Chapter Exercises: Motion in One Dimension . . . . . . . . . . . . . . . 192 12 Gravity and Mechanical Energy - Grade 10 197 12.1 Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197 12.1.1 Differences between Mass and Weight . . . . . . . . . . . . . . . . . . . 198 12.2 Acceleration due to Gravity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199 12.2.1 Gravitational Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199 12.2.2 Free fall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199 12.3 Potential Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 12.4 Kinetic Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206 12.4.1 Checking units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207 12.5 Mechanical Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208 12.5.1 Conservation of Mechanical Energy . . . . . . . . . . . . . . . . . . . . . 208 12.5.2 Using the Law of Conservation of Energy . . . . . . . . . . . . . . . . . 209 12.6 Energy graphs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213 12.7 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214 12.8 End of Chapter Exercises: Gravity and Mechanical Energy . . . . . . . . . . . . 214 13 Transverse Pulses - Grade 10 217 13.1 Introducti on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217 13.2 What is a medium? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217 ix CONTENTS CONTENTS 13.3 What is a pulse? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217 13.3.1 Pulse Length and Amplitude . . . . . . . . . . . . . . . . . . . . . . . . 218 13.3.2 Pulse Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219 13.4 Graphs of Position and Velocity . . . . . . . . . . . . . . . . . . . . . . . . . . . 220 13.4.1 Motion of a Particle of the Medium . . . . . . . . . . . . . . . . . . . . 220 13.4.2 Motion of the Pulse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222 13.5 Transmission and Reflection of a P u lse at a Boundary . . . . . . . . . . . . . . . 226 13.6 Reflection of a Pulse from Fixed and Free Ends . . . . . . . . . . . . . . . . . . 228 13.6.1 Reflection of a Pulse from a Fixed End . . . . . . . . . . . . . . . . . . . 228 13.6.2 Reflection of a Pulse from a Free End . . . . . . . . . . . . . . . . . . . 228 13.7 Superposition of Pulses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229 13.8 Exercises - Transverse Pulses . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232 14 Transverse Waves - Grade 10 235 14.1 Introducti on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235 14.2 What is a transverse wave? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235 14.2.1 Peaks and Troughs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236 14.2.2 Amplitude and Wavelength . . . . . . . . . . . . . . . . . . . . . . . . . 237 14.2.3 Points in Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 14.2.4 Period and Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240 14.2.5 Speed of a Transverse Wave . . . . . . . . . . . . . . . . . . . . . . . . 241 14.3 Graphs of Particle Motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245 14.4 Standing Waves and Boundary Conditions . . . . . . . . . . . . . . . . . . . . . 248 14.4.1 Reflection of a Transverse Wave from a Fixed End . . . . . . . . . . . . 248 14.4.2 Reflection of a Transverse Wave from a Free End . . . . . . . . . . . . . 248 14.4.3 Standing Waves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 14.4.4 Nodes and Anti-nodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252 14.4.5 Wavelengths of Standing Waves with Fixed and Free Ends . . . . . . . . 252 14.4.6 Superposition and Interference . . . . . . . . . . . . . . . . . . . . . . . 255 14.5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257 14.6 Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257 15 Geometrical Optics - Grade 10 259 15.1 Introducti on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259 15.2 Light Rays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259 15.2.1 Shadows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261 15.2.2 Ray Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261 15.3 Reflection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262 15.3.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262 15.3.2 Law of Reflection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262 15.3.3 Types of Reflection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 15.4 Refraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266 x [...]... one For example M means mega (106 ) and m means milli (10 3 ) 8 CHAPTER 1 UNITS Prefix yotta zetta exa peta tera giga mega kilo hecto deca 1.6 Symbol Y Z E P T G M k h da Exponent 102 4 102 1 101 8 101 5 101 2 109 106 103 102 101 Prefix yocto zepto atto femto pico nano micro milli centi deci Symbol y z a f p n µ m c d Exponent 10 24 10 21 10 18 10 15 10 12 10 9 10 6 10 3 10 2 10 1 Table 1.4: Unit Prefixes Important:... (micromol) Exercise: Using Scientific Notation 1 Write the following in scientific notation using Table 10. 4 as a reference (a) 0,511 MV (b) 10 c (c) 0,5 µm (d) 250 nm (e) 0,00035 hg 2 Write the following using the prefixes in Table 10. 4 (a) 1,602 10 19 C (b) 1,992 106 J (c) 5,98 104 N (d) 25 10 4 A (e) 0,0075 106 m 9 1.7 1.7 CHAPTER 1 UNITS The Importance of Units Without units much of our work as scientists... is a useful skill in Science 10 CHAPTER 1 UNITS 1.8 The following conversion diagrams will help you change from one unit to another 100 0 100 0 m mm 100 0 km 100 0 Figure 1.1: The distance conversion table If you want to change millimetre to metre, you divide by 100 0 (follow the arrow from mm to m); or if you want to change kilometre to millimetre, you multiply by 100 0 100 0 The same method can be used... Giving names and formulae to substances It is easy to describe elements and mixtures But how are compounds named? In the example of iron sulfide that was used earlier, which element is named first, and which ’ending’ is given to the compound name (in this case, the ending is -ide)? The following are some guidelines for naming compounds: 22 CHAPTER 2 CLASSIFICATION OF MATTER - GRADE 10 2.3 1 The compound name... The same method can be used to change millilitre to litre or kilolitre Use figure 10. 2 to change volumes: 100 0 m cm3 100 0 k m3 dm3 100 0 100 0 Figure 1.2: The volume conversion table Worked Example 3: Conversion 1 Question: Express 3 800 mm in metres Answer Step 1 : Find the two units on the conversion diagram Use Figure 10. 1 Millimetre is on the left and metre in the middle Step 2 : Decide whether... kilogram (kg) is a simple example 1 kg is equal to 1 000 g or 1 × 103 g Grouping the 103 and the g together we can replace the 103 with the prefix k (kilo) Therefore the k takes the place of the 103 The kilogram is unique in that it is the only SI base unit containing a prefix In Science, all the prefixes used with units are some power of 10 Table 10. 4 lists some of these prefixes You will not use most of these... Category People Transport General 1 .10 Quantity mass height speed of cars on freeways speed of trains speed of aeroplanes distance between home and school thickness of a sheet of paper height of a doorway Minimum Maximum Summary 1 You need to know the seven base SI Units as listed in table 10. 1 Combinations of SI Units can have different names 12 CHAPTER 1 UNITS 1 .10 2 Unit names and abbreviations are written... 40000 m can be written as 40 km (kilometre) • 0,001 g is the same as 1 × 10 3 g and can be written as 1 mg (milligram) • 2,5 × 106 N can be written as 2,5 MN (meganewton) • 250000 A can be written as 250 kA (kiloampere) or 0,250 MA (megaampere) • 0,000000075 s can be written as 75 ns (nanoseconds) • 3 10 7 mol can be rewritten as 0,3 10 6 mol, which is the same as 0,3 µmol (micromol) Exercise: Using Scientific... metre and for litre The exception to this rule is if the unit is named after a person, then the symbol is a capital letter For example, the kelvin was named after Lord Kelvin and its symbol is K If the abbreviation of the unit that is named after a person has two letters, the second letter is lowercase, for example Hz for hertz Exercise: Naming of Units For the following symbols of units that you will... have different names 12 CHAPTER 1 UNITS 1 .10 2 Unit names and abbreviations are written with lowercase letter unless it is named after a person 3 Rounding numbers and using scientific notation is important 4 Table 10. 4 summarises the prefixes used in Science 5 Use figures 10. 1 and 10. 2 to convert between units 13 1.11 CHAPTER 1 UNITS 1.11 End of Chapter Exercises 1 Write down the SI unit for the each of . kg is equal to 1 000 g or 1 × 10 3 g. Grouping the 10 3 and the g together we can replace the 10 3 with the prefix k (kilo). Therefore the k takes the place of the 10 3 . The kilogram is unique. . 103 7.5 The unique properties of water . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 7.6 Water conservation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 7.7. . . . . . . . . . . . . . . . 137 9 .10 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 II Physics 141 10 Units 143 10. 1 Introducti on . . . . . . . .