Nelson Physics 12: University Preparation

748 Pages·2012·76.86 MB·English

by  Dan Bruni

AUTHOR TeAm
Dan Bruni, B.Sc., M.Sc., B.Ed.
York Catholic District School Board
Greg Dick, B.Sc. (Hons), B.Ed., OCT
Perimeter Institute for Theoretical Physics
Jacob Speijer, B.Eng., M.Sc.Ed., P.Eng., OCT
Simcoe County District School Board
Charles Stewart, B.Sc., B.Ed.
Peel District School Board
SeniOR PROgRAm COnSUlTAnT
Maurice DiGiuseppe, Ph.D.
University of Ontario Institute of Technology (UOIT)
Formerly Toronto Catholic District School Board
PROgRAm COnSUlTAnT
Charles Stewart, B.Sc., B.Ed.
Peel District School Board
8160_FM_pi-vii.indd 1 4/12/12 10:04 AM
Nelson physics 12
Senior program Consultant Authors Contributing Authors
Maurice DiGiuseppe Dan Bruni Stefanie Clark
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Reviewers
Accuracy Reviewers Safety Consultants Martin Gabber
Deepak Chandan Jim Agban Formerly of Durham DSB
University of Toronto, Department Past Chair, Science Teachers’
Shawna Hopkins
of Physics Association of Ontario (STAO)
Niagara DSB
Safety Committee
Richard Epp
Christopher T. Howes
Perimeter Institute for Theoretical Peter Cudmore
Durham DSB
Physics, Scientific Outreach Chair, Science Teachers’ Association
Manager of Ontario (STAO) Safety
Patricia Jones
Committee
Ottawa–Carleton DSB
Martin Williams Renfrew County District School Board
University of Guelph, Department
Roche Kelly
of Physics
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Alistair MacLeod Dermot O’Hara
Limestone DSB Karen Iverson Toronto Catholic DSB
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Steve Pfisterer
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Advisory Panel and Teacher
Ted Laxton
Reviewers Robert Pickett
Faculty of Education, Wilfred Laurier
Catholic DSB of Eastern Ontario
University Anca Bogorin
Formerly Wellington Catholic DSB Avon Maitland DSB Ron Ricci
Greater Essex County DSB
Racquel Carlow
eSl Consultant Dufferin–Peel Catholic DSB Henri van Bemmel
Paula Markus Toronto DSB
Andrew Cherkas
ESL/ELD Program Coordinator,
York Region DSB
Rob Vucic
Toronto DSB
Peel DSB
Charles J. Cohen
Tanenbaum Community Hebrew
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numeracy Consultant
Academy of Toronto
Upper Grand DSB
Mary Bourassa
Ottawa–Carleton DSB Matthew Di Fiore Victoria Wraight
Dufferin–Peel Catholic DSB
Kawartha Pine Ridge Board
of Education
STSe Consultant Naomi Epstein
Tanenbaum Community Hebrew
Joanne Nazir Jim Young
Academy of Toronto
Ontario Institute for Studies in Limestone DSB
Education (OISE),
Dave Fish
University of Toronto Waterloo Region DSB
Reviewers iii
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Contents
Unit 1 Dynamics . . . . . . . . . . . . . . . 2 Chapter 3: Uniform Circular Motion . . . . . . 106
3 .1 Inertial and Non-inertial Frames
Focus on STSe: Applying the Dynamics
of Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108
of motion . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
3 .2 Centripetal Acceleration . . . . . . . . . . . . . . . . . . . .114
Are You Ready? . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
3 .3 Centripetal Force . . . . . . . . . . . . . . . . . . . . . . . . . .120
Chapter 1: Kinematics . . . . . . . . . . . . . . . . . . 6 3 .4 Rotating Frames of Reference . . . . . . . . . . . . . . . .125
1 .1 Motion and Motion Graphs . . . . . . . . . . . . . . . . . . .8 3 .5 Physics Journal: The Physics
of Roller Coasters . . . . . . . . . . . . . . . . . . . . . . . . . .131
1 .2 Equations of Motion . . . . . . . . . . . . . . . . . . . . . . . .17
3 .6 explore an issue in Dynamics:
1 .3 Displacement in Two Dimensions . . . . . . . . . . . . .22
Improvements in Athletic Technology . . . . . . . .133
1 .4 Velocity and Acceleration in Two Dimensions . .30
investigation 3 .3 .1: Simulating Uniform
1 .5 Projectile Motion . . . . . . . . . . . . . . . . . . . . . . . . . . .36 Circular Motion . . . . . . . . . . . . . . . . . . . . . . . . . . .135
1 .6 Relative Motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44 investigation 3 .3 .2: Analyzing Uniform
investigation 1 .5 .1: Investigating Projectile Circular Motion . . . . . . . . . . . . . . . . . . . . . . . . . . .136
Motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 Chapter 3 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . .138
Chapter 1 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52 Chapter 3 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . . . .139
Chapter 1 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53 Chapter 3 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140
Chapter 1 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
Unit 1 Task: A new extreme Sport . . . . . . . . . .146
Chapter 2: Dynamics . . . . . . . . . . . . . . . . . 60
Unit 1 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . .148
2 .1 Forces and Free-Body Diagrams . . . . . . . . . . . . . .62 Unit 1 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . .150
2 .2 Newton’s Laws of Motion . . . . . . . . . . . . . . . . . . . .70
2 .3 Applying Newton’s Laws of Motion . . . . . . . . . . . .77
2 .4 Forces of Friction . . . . . . . . . . . . . . . . . . . . . . . . . . .84 Unit 2 energy and momentum . . 158
2 .5 explore an Application in Dynamics:
Focus on STSe: innovations
Linear Actuators . . . . . . . . . . . . . . . . . . . . . . . . . . . .91
in energy Technology . . . . . . . . . . . . . . .159
2 .6 Physics Journal: The Physics
Are You Ready? . . . . . . . . . . . . . . . . . . . . . . . . . .160
of Downhill Skiing . . . . . . . . . . . . . . . . . . . . . . . . . .93
investigation 2 .3 .1: Static Equilibrium
Chapter 4: Work and Energy . . . . . . . . . . . 162
of Forces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95
4 .1 Work Done by a Constant Force . . . . . . . . . . . . .164
investigation 2 .4 .1: Inclined Plane
and Friction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96 4 .2 Kinetic Energy and
the Work-Energy Theorem . . . . . . . . . . . . . . . . . .171
investigation 2 .4 .2: Motion and Pulleys . . . . . . . . . . . . .97
Chapter 2 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98 4 .3 Gravitational Potential Energy . . . . . . . . . . . . . . .177
Chapter 2 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99 4 .4 explore an issue in energy generation:
Gravitational Potential Energy
Chapter 2 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100
and Hydroelectricity . . . . . . . . . . . . . . . . . . . . . . .182
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4 .5 The Law of Conservation of Energy . . . . . . . . . .184 Unit 3 gravitational, electric,
4 .6 Elastic Potential Energy and magnetic Fields . . . . . . . . . . . 282
and Simple Harmonic Motion . . . . . . . . . . . . . . .192
4 .7 Springs and Conservation Focus on STSe: The international
Space Station . . . . . . . . . . . . . . . . . . . . . .283
of Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201
Are You Ready? . . . . . . . . . . . . . . . . . . . . . . . . . .284
investigation 4 .2 .1: The Work–Energy
Theorem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209
Chapter 6: Gravitational Fields . . . . . . . . . 286
investigation 4 .5 .1: Energy and Pulleys . . . . . . . . . . . .210
investigation 4 .7 .1: Energy and Springs . . . . . . . . . . . .211 6 .1 Newtonian Gravitation . . . . . . . . . . . . . . . . . . . . .288
Chapter 4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . .212 6 .2 Orbits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .297
Chapter 4 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . . . .213 6 .3 explore Applications
of gravitational Fields: Satellites . . . . . . . . . . .304
Chapter 4 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214
6 .4 Physics Journal: General Relativity . . . . . . . . . . .306
Chapter 5: Momentum and Collisions . . . . 220 investigation 6 .1 .1: Universal Gravitation . . . . . . . . . .308
5 .1 Momentum and Impulse . . . . . . . . . . . . . . . . . . . .222 investigation 6 .2 .1: Design a Solar System . . . . . . . . . .309
5 .2 Conservation of Momentum Chapter 6 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . .310
in One Dimension . . . . . . . . . . . . . . . . . . . . . . . . .228 Chapter 6 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . . . .311
5 .3 Collisions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233 Chapter 6 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .312
5 .4 Head-on Elastic Collisions . . . . . . . . . . . . . . . . . .240
5 .5 Collisions in Two Dimensions: Chapter 7: Electric Fields . . . . . . . . . . . . . 318
Glancing Collisions . . . . . . . . . . . . . . . . . . . . . . . .249
7 .1 Properties of Electric Charge . . . . . . . . . . . . . . . .320
5 .6 explore Applications of momentum:
7 .2 Coulomb’s Law . . . . . . . . . . . . . . . . . . . . . . . . . . . .327
Staying Safe at Every Speed . . . . . . . . . . . . . . . . . .254
7 .3 Electric Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . .334
5 .7 Physics Journal: Momentum
and the Neutrino . . . . . . . . . . . . . . . . . . . . . . . . . .256 7 .4 Potential Difference
and Electric Potential . . . . . . . . . . . . . . . . . . . . . . .346
investigation 5 .2 .1: Conservation
of Momentum in One Dimension . . . . . . . . . . . .258 7 .5 Electric Potential and Electric Potential
Energy Due to Point Charges . . . . . . . . . . . . . . . .355
investigation 5 .4 .1: Head-on Elastic Collisions . . . . . .259
7 .6 The Millikan Oil Drop Experiment . . . . . . . . . . .362
investigation 5 .5 .1: Conservation
of Momentum in Two Dimensions . . . . . . . . . . .260 investigation 7 .2 .1: Coulomb’s Law . . . . . . . . . . . . . . . .366
Chapter 5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . .262 investigation 7 .6 .1: The Millikan Experiment . . . . . . .367
Chapter 5 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . . . .263 Chapter 7 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . .368
Chapter 5 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264 Chapter 7 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . . . .369
Chapter 7 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .370
Unit 2 Task: Applications of energy and
momentum in engineering Design . . . . .270
Unit 2 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . .272
Unit 2 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . .274
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Chapter 8: Magnetic Fields . . . . . . . . . . . . 376 investigation 9 .3 .1: Properties of Water Waves . . . . . .487
8 .1 Magnets and Electromagnets . . . . . . . . . . . . . . . .378 investigation 9 .3 .2: Interference of Waves
in Two Dimensions . . . . . . . . . . . . . . . . . . . . . . . .488
8 .2 Magnetic Force on Moving Charges . . . . . . . . . .386
investigation 9 .5 .1: Young’s Double-Slit
8 .3 Magnetic Force on a Current-Carrying
Experiment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .490
Conductor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .392
Chapter 9 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . .492
8 .4 Motion of Charged Particles in
Chapter 9 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . . . .493
Magnetic Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . .397
8 .5 Applications of Electric and Chapter 9 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .494
Magnetic Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . .405
Chapter 10: Applications of the Wave
8 .6 explore an Application
Nature of Light . . . . . . . . . . . . . . . . . . . . . . 500
in electromagnetic Fields:
Particle Accelerators . . . . . . . . . . . . . . . . . . . . . . . .410 10 .1 Interference in Thin Films . . . . . . . . . . . . . . . . . .502
investigation 8 .2 .1: Observing the Magnetic 10 .2 Single-Slit Diffraction . . . . . . . . . . . . . . . . . . . . . .512
Force on a Moving Charge . . . . . . . . . . . . . . . . . .412 10 .3 The Diffraction Grating . . . . . . . . . . . . . . . . . . . . .520
Chapter 8 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . .414 10 .4 Electromagnetic Radiation . . . . . . . . . . . . . . . . . .526
Chapter 8 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . . . .415 10 .5 Polarization of Light . . . . . . . . . . . . . . . . . . . . . . . .532
Chapter 8 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .416 10 .6 explore Applications of light
Technology: Electromagnetic Waves . . . . . . . . .538
Unit 3 Task: Field Technology in Use . . . . . . . . .422
10 .7 Physics Journal: Light Nanotechnology and
Unit 3 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . .424 Counterfeit Prevention . . . . . . . . . . . . . . . . . . . . .540
Unit 3 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . .426 10 .8 explore an issue in light Technology:
Global Positioning Systems . . . . . . . . . . . . . . . . . .542
Unit 4 The Wave nature investigation 10 .1 .1: Investigating Interference
Using Air Wedges . . . . . . . . . . . . . . . . . . . . . . . . . .544
of light . . . . . . . . . . . . . . . . . . . . . . 434
investigation 10 .2 .1: Diffraction of Light
Focus on STSe: light and interference . . . . . .435 Using a Single Slit . . . . . . . . . . . . . . . . . . . . . . . . . .545
Are You Ready? . . . . . . . . . . . . . . . . . . . . . . . . . .436 investigation 10 .3 .1: CD and DVD
Storage Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . .547
Chapter 9: Waves and Light . . . . . . . . . . . 438 Chapter 10 Summary . . . . . . . . . . . . . . . . . . . . . . . . . .548
9 .1 Properties of Waves and Light . . . . . . . . . . . . . . .440 Chapter 10 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . . .549
9 .2 Refraction and Total Internal Reflection . . . . . .444 Chapter 10 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . .550
9 .3 Diffraction and Interference
Unit 4 Task: Optical Pattern Analysis . . . . . . . .556
of Water Waves . . . . . . . . . . . . . . . . . . . . . . . . . . . .459
Unit 4 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . .558
9 .4 Light: Wave or Particle? . . . . . . . . . . . . . . . . . . . . .470
Unit 4 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . .560
9 .5 Interference of Light Waves:
Young’s Double-Slit Experiment . . . . . . . . . . . . .477
9 .6 explore an issue in light-Based
Technology: Should Governments
Restrict Network Access? . . . . . . . . . . . . . . . . . . .485
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Unit 5 Revolutions in modern 12 .5 Physics Journal: Raymond Laflamme and
Physics: Quantum mechanics Quantum Information Theory . . . . . . . . . . . . . . .642
12 .6 The Standard Model of Elementary Particles . . .644
and Special Relativity . . . . . . . . . . 568
investigation 12 .2 .1: The Photoelectric Effect . . . . . . .654
Focus on STSe: Particle Acceleration investigation 12 .2 .2: Determining Planck’s
and the large Hadron Collider . . . . . . . .569 Constant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .656
Are You Ready? . . . . . . . . . . . . . . . . . . . . . . . . . .570 investigation 12 .6 .1: Laser Simulation . . . . . . . . . . . . .657
Chapter 12 Summary . . . . . . . . . . . . . . . . . . . . . . . . . .658
Chapter 11: Relativity . . . . . . . . . . . . . . . . 572
Chapter 12 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . . .659
11 .1 The Special Theory of Relativity . . . . . . . . . . . . . .574 Chapter 12 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . .660
11 .2 Time Dilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .580
Unit 5 Task: The large Hadron Collider:
11 .3 Length Contraction, Simultaneity,
The World’s Biggest microscope . . . . . .666
and Relativistic Momentum . . . . . . . . . . . . . . . . .588
Unit 5 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . .668
11 .4 Mass–Energy Equivalence . . . . . . . . . . . . . . . . . . .598
Unit 5 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . .670
investigation 11 .2 .1: Analyzing Relativistic Data . . . .604
Chapter 11 Summary . . . . . . . . . . . . . . . . . . . . . . . . . .606
Appen dix A Skills Handbook . . . . . . . . . . . . .679
Chapter 11 Self-Quiz . . . . . . . . . . . . . . . . . . . . . . . . . . .607
Chapter 11 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . .608
Appen dix B Reference . . . . . . . . . . . . . . . . . . .708
Chapter 12: Quantum Mechanics . . . . . . . 614
Appen dix C Answers . . . . . . . . . . . . . . . . . . . .714
12 .1 Introducing Quantum Theory . . . . . . . . . . . . . . .616
12 .2 Photons and the Quantum Theory of Light . . . .620 glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .723
12 .3 Wave Properties of Classical Particles . . . . . . . . .632 index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .730
12 .4 explore an Application in Quantum Credits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xxx
mechanics: Medical Diagnostic Tools . . . . . . .640
Contents vii
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1
T
I
N dynamics
U
oVeRAll
eXpectAtions
• analyze technological devices that
apply the principles of the dynamics of
motion, and assess the technologies’
social and environmental impact
• investigate, in qualitative and
quantitative terms, forces involved in
uniform circular motion and motion in
a plane, and solve related problems
• demonstrate an understanding of the
forces involved in uniform circular
motion and motion in a plane
Big iDeAs
• Forces affect motion in predictable
and quantifi able ways.
• Forces acting on an object will
determine the motion of that object.
• Many technologies that utilize the
principles of dynamics have societal
and environmental implications.
UNiT TASK PrEvIEw
In the Unit Task, you will apply some of the principles of physics
that are used in sports and games. The Unit Task is described in
detail on page 146. As you work through the unit, look for Unit
Task Bookmarks to see how information in the section relates
to the Unit Task.
2 Unit 1 • Dynamics
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Focus on STSE
Applying the DynAmics oF motion
One of the most exciting and dangerous winter sports is the one-person luge (sled),
where athletes race down icy tracks with high banked curves on top of a small luge, as
seen in the image on the facing page.
The thrill of the luge comes from the high levels of speed the athlete can reach. To
help reduce air resistance and reach high speeds, athletes try to be as aerodynamic as
possible by lying down and keeping their heads down and toes pointed. They also wear
specially designed aerodynamic racing helmets and suits and use lightweight luges. In
fact, many racers spend hours in wind tunnels designed to help them find the ideal body
position to minimize drag.
The terrain and the mass of the luge also affect the speed. The steeper the hill, the faster
the luge goes. However, if the luge crashes, the impact will be greater as well. The smoother
the track, the less friction between the ice and the sled, and the faster the luge will go. The
only brakes are the athlete’s feet. Their shoes are covered with treads, like tire treads, to
help protect them from the tremendous amount of friction created by braking.
The most dangerous points on a luge run are the turns and turn combinations, where
circular motion and high velocities buffet the athlete. To maintain speed, the athlete must
find just the right spot on the luge to perfectly balance the opposing forces.
Think about all the different kinds of motion and forces that occur as the luger speeds
down the track. Which forces, if any, do you think have no direct effect on the motion of
the luge? Which forces speed it up or slow it down? Gravity pulls the luger down the track,
but some of this force is balanced by the other forces acting on the luge. For example,
friction between the sled and the track works against gravity.
Questions
1. Which features of the luge and the athlete’s technique help decrease the time
of the run?
2. Why are the turns banked? Explain what you know about the forces acting on the
athlete in the turns.
3. What are the main forces that cause the luge to speed up? When do the largest
accelerations occur?
4. In what direction is the net force on the luge and the athlete when going around a
banked curve? Explain your reasoning.
5. The sport of luging is extremely dangerous. In your opinion, should more stringent
conditions or rules be implemented for luge courses? Explain your reasoning.
Focus on STSE 3
NEL
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