Physics : concepts and connections

537 Pages·2014·19.912 MB·English

by  Hobson, Art

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ISBN 978-1-29203-958-9 e
9 781292 039589
Pearson New International Edition

Physics:
Concepts and Connections
Art Hobson
Fifth Edition
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ISBN 13: 978-1-292-03958-9
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ISBN 10: 1-292-03958-2
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P E A R S O N C U S T O M L I B R AR Y
Table of Contents
Glossary
Art Hobson 1
1. The Way of Science: Experience and Reason
Art Hobson 15
Problem Set (5/e): The Way of Science: Experience and Reason
Art Hobson 45
2. Atoms: The Nature of Things
Art Hobson 49
Problem Set (5/e): Atoms: The Nature of Things
Art Hobson 67
3. How Things Move: Galileo Asks the Right Questions
Art Hobson 71
Problem Set (5/e): How Things Move: Galileo Asks the Right Questions
Art Hobson 87
4. Why Things Move as They Do
Art Hobson 93
Problem Set (5/e): Why Things Move as They Do
Art Hobson 113
5. Newton’s Universe
Art Hobson 119
Problem Set (5/e): Newton’s Universe
Art Hobson 141
6. Conservation of Energy: You Can’t Get Ahead
Art Hobson 145
Problem Set (5/e): Conservation of Energy: You Can’t Get Ahead
Art Hobson 161
I
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7. Second Law of Thermodynamics
Art Hobson 167
Problem Set (5/e): Second Law of Thermodynamics
Art Hobson 193
8. Electromagnetism
Art Hobson 199
Problem Set (5/e): Electromagnetism
Art Hobson 221
9. Waves, Light, and Climate Change
Art Hobson 227
Problem Set (5/e): Waves, Light, and Climate Change
Art Hobson 261
10. The Special Theory of Relativity
Art Hobson 269
Problem Set (5/e): The Special Theory of Relativity
Art Hobson 293
11. Einstein’s Universe and the New Cosmology
Art Hobson 299
Problem Set (5/e): Einstein’s Universe and the New Cosmology
Art Hobson 321
12. The Quantum Idea
Art Hobson 325
Problem Set (5/e): The Quantum Idea
Art Hobson 343
13. The Quantum Universe
Art Hobson 347
Problem Set (5/e): The Quantum Universe
Art Hobson 375
14. The Nucleus and Radioactivity: A New Force
Art Hobson 383
Problem Set (5/e): The Nucleus and Radioactivity: A New Force
Art Hobson 405
15. The Energy Challenge
Art Hobson 411
Problem Set (5/e): The Energy Challenge
Art Hobson 441
II
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16. Fusion and Fission—and a New Energy
Art Hobson 449
Problem Set (5/e): Fusion and Fission—and a New Energy
Art Hobson 473
17. Quantum Fields: Relativity Meets the Quantum
Art Hobson 477
Problem Set (5/e): Quantum Fields: Relativity Meets the Quantum
Art Hobson 505
18. Summing Up
Art Hobson 511
Periodic Table of the Elements
Art Hobson 515
Flow Chart of Topics
Art Hobson 517
Index 519
III
IV
GLOSSARY
A-bomb See fission bomb. Aristotle’s physics Plausible notions that have since been discarded
AC See alternating current. by both Newtonian and modern physics. Aristotle believed that there
accelerating universe Observations of distant supernova explo- were three kinds of motion: natural, violent, and celestial.
sions show rather conclusively that the universe is not only artificial radiation Ionizing radiation from artificial sources
expanding but is expanding at an ever-increasing speed. such as medical sources. See also natural radiation.
acceleration An accelerated object is one whose velocity is astrology The belief, rejected by science for over two centuries,
changing. Quantitatively, the acceleration is the change in veloc- that events on Earth are influenced by the positions and motions
ity during a time interval divided by the duration of that time of the planets.
interval. It can be measured in (km/hr)/s, or in (m s) s = m s2. astronomy The scientific study of the stars and other objects
> > >
acceleration due to gravity The acceleration of any freely inspace.
falling object. On Earth this is about 10 m s2or, more precisely, atom See chemical element.
9.8 m s2. > atomic bomb See fission bomb.
>
action-reaction cycle A mutually reinforcing cycle of increased atomic number The number of protons in an atom. Also the
armaments by two or more hostile nations. number of electrons in a neutral atom. An atom’s atomic number
active solar energy Energy provided by a solar-heated liquid or determines its chemical properties and the element to which it
gas that is pumped to a location where it can be used for space or belongs.
water heating. atomic theory of matter All matter is made of tiny particles, too
air A mixture of several chemical compounds: nitrogen (N2, small to be seen.
about 80%), oxygen (O2, about 20%), argon (Ar, about 1%), and atomism The notion that nature can be reduced to the motion of
a smattering of trace gases. tiny material particles.
air resistance The resistive force that air molecules exert on an average speed An object’s average speed is its distance traveled
object moving through the air. during a time interval divided by the duration of that time interval.
alpha decay One type of radioactive decay. The spontaneous Measured in meters per second. See also instantaneous speed.
emission, by a nucleus, of an alpha particle (a helium nucleus that
breaks off of a larger nucleus). beta decay The other main type of radioactive decay. The spon-
alpha particle See alpha decay. taneous emission, by a nucleus, of a beta particle (an electron
alpha rays, beta rays, gamma rays The streams of particles that created in the nucleus). See also alpha decay.
are emitted by a macroscopic sample of radioactive material. beta particle See beta decay.
alternating current An electric current that reverses its direc- beta rays See alpha rays.
tion of flow many times every second. big bang The event some 14 billion years ago that created time,
amp orampere The measurement unit for electric current. One space, matter, and the different forms of energy, and started the
amp is defined as a flow of 1 coulomb per second. expansion of the universe.
amplitude The maximum disturbance in a wave; the maximum biofuel Biomass (organic substances) that has been processed
deviation from the undisturbed state of the medium. to make transportation or other fuels.
anthropic principle The idea that our universe must be organ- biology and the second law of thermodynamics The entropy of
ized in the way that it is because any other organization would a growing plant decreases at the expense of a far greater entropy
not allow intelligent beings to be here to ask the question in the increase in the absorbed and reradiated solar energy that passes
first place. through the plant. A similar situation exists for all biological
antielectron See positron. processes, including the evolution of species.
antimatter Made of antiprotons, antineutrons, and positrons. biomass energy The chemical energy of organic substances.
Today’s universe consists overwhelmingly of matter, not antimatter. bit See quantum computer.
antineutron Antiparticle of the neutron. See also antiparticle. black hole Any object whose matter (mass) has gravitationally
antiparticle The theory of special relativity requires that for collapsed into a single point. Nothing can escape from its vicin-
every existing type of particle, there is an antiparticle carrying ity. When very massive stars run out of fuel, they explode, and the
the opposite charge. Quantum uncertainties allow the creation remnant collapses to become a black hole. Giant black holes exist
and annihilation of particle–antiparticle pairs such as at the centers of most galaxies, including ours.
electron–positron pairs. breeder reactor A reactor that creates more than one 239Pu
antiproton Antiparticle of the proton. See also antiparticle. nucleus (from 238U) for each 235Unucleus it fissions and so cre-
Aristarchus’s hypothesis A sun-centered theory that was ates more fuel than it uses.
rejected because it seemed to conflict with everyday observations. Brownian motion The erratic motion of a microscopic dust or
Aristotelian physics, difficulties Contrary to Aristotelian pre- pollen grain immersed in a liquid or gas, caused by numerous
dictions, heavy and light objects often fall at the same accelera- moving atoms or molecules colliding with the grain every second.
tion, and horizontally moving objects would move forever if there bubble chamber See cloud chamber.
were no external forces. burning This chemical reaction creates warmth by combining
oxygen from air with a fuel such as carbon or hydrogen.
1
GLOSSARY
C See coulomb. chlorofluorocarbons (CFCs) Chemicals whose molecules are
Calorie The amount of work (or energy) needed to raise the made of chlorine, fluorine, and carbon. Manufactured as
temperature of 1 kilogram of water by 1°C. coolants, spray propellants, foaming agents, and solvents. They
cap and trade See carbon cap and trade. destroy stratospheric ozone.
carbon cap and trade One suggested way to incorporate the climate model Computer calculations based on accepted princi-
cost of global warming into the cost of products and thus reduce ples of physics, chemistry, and other science that predict climatic
CO emissions. An overall limit (cap) would be placed on total conditions on Earth’s surface and throughout the atmosphere for
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carbon emissions, and “tradable permits” to emit a certain many years into the future, at each point of a three-dimensional
amount of CO (adding up to the allowed cap) would be issued to grid of points separated by several hundred kilometers.
2
carbon-emitting companies. Companies could buy and sell per- closed universe See geometry of the universe.
mits among themselves, so that less efficient companies would be cloud chamber A device that shows the path of a charged parti-
able to buy additional permits from more efficient companies. cle as a trail of droplets in water vapor. Its successor, the bubble
carbon capture and storage The process of capturing CO2from chamber, shows a particle’s path as a trail of bubbles in a liquid.
fossil-fuel-fired generating plants, compressing it, piping it to a cogeneration The simultaneous production of electricity and
storage facility, and permanently storing it underground. useful thermal energy.
carbon dating A radioactive dating method in which radioac- collapse of a wave packet The instantaneous reduction in the
tive 14Cin a dead organism is measured as a fraction of the total size of a wave packet that occurs when a particle’s position is
carbon in order to determine how long the 14Chas been decaying measured. See also wave packet.
and when the organism died. combined heat and power See cogeneration.
carbon tax One suggested way of incorporating the cost of compact fluorescent bulb See fluorescent bulb.
global warming into the cost of products and thus reducing CO2 conduction electrons The outermost one or two electrons in the
emissions. Companies would be taxed a certain amount for each atoms of any metal. These electrons move easily through the
tonne of CO they emit. metal when subjected to even a small electric force.
2
cellulosic biomass Biomass from non-edible organic materials conductor See electrical conductor.
such as grasses, paper products, wood, agricultural waste, and conservation of charge See law of conservation of charge.
municipal solid waste. conservation of energy See law of conservation of energy.
centimeter (cm) One-hundredth of a meter. conservation of matter The total amount of matter involved in
centrifuge separation One way, widely used today, to enrich any chemical reaction, or in any other physical process, is the
uranium. See also uranium enrichment. same after the reaction as it was before. Although it is a useful
CFC See chlorofluorocarbons. principle, experiments have proved that it is only a useful approx-
chain reaction A series of neutron-induced fission reactions imation in chemical reactions, and entirely wrong in many
that proceed from one nucleus to the next by means of the neu- othersituations.
trons released during each fission reaction. conservation of momentum See law of conservation of
charge See electrically charged object. momentum.
chemical compound A pure substance that can be chemically constructive interference See interference.
decomposed. Its smallest particle is a molecule, two or more containment dome See nuclear power reactor.
atoms connected into a single unit. All of a compound’s mole- continuous spectrum A spectrum containing a continuous
cules are identical. range of frequencies. See also spectrum.
chemical decomposition Any process that changes a single control rods See nuclear power reactor.
substance into two or more other substances. coolant See nuclear power reactor.
chemical element One of the approximately 116 different sub- Copernican revolution The rejection of the idea that Earth is at
stances that cannot be chemically decomposed. An atom whose the center of, and therefore basically different from, the rest of
nucleus has a specific atomic number (number of protons), the universe.
regardless of how many neutrons it might have. The elements are Copernican viewpoint The view that Earth is not a unique place
listed in the periodic table. An atom is the smallest particle of in the universe, that the same principles of nature apply through-
anelement. out the universe. For example, since intelligent life occurred here,
chemical energy Energy due to molecular structure. this view argues that it also should have occurred elsewhere.
chemical origin of life See hypothesis of a chemical origin of life. Copernicus’s theory A sun-centered theory, similar to
chemical reaction A rearrangement of the atoms in molecules Aristarchus’s. The planets, including Earth, circle the sun, and
into new molecular forms. For examples, see burning, Earth spins on its axis.
respiration, and photosynthesis. cosmic inflation A widely respected hypothesis of the details of
chemically inert Does not participate readily in chemical reactions. how the big bang occurred. According to this hypothesis, during a
chemistry The study of the properties and transformations of short period in the very early universe, the universe expanded
substances (chemical compounds). enormously at a speed greater than lightspeed. This “inflation”
Chernobyl Site of world’s worst nuclear power accident. The stretched the universe to many times the size it had before the
fuel melted down, the reactor suffered a “slow nuclear explo- inflationary process began, flattening the geometry of the uni-
sion,” and a large amount of radioactivity escaped. A few tens of verse and creating the mass and energy observed today.
people were killed from short-term effects, and about 4000 are
expected to die of long-term cancers. See also meltdown.
2
GLOSSARY
cosmic microwave background The faint microwave remnant double-slit experiment with electrons When an electron beam
of the high-energy radiation from the big bang that still fills the passes through two narrow slits and strikes a viewing screen, an
universe. interference pattern is observed. This demonstrates that an elec-
cosmic rays High-energy particles that travel through outer tron beam is a wave. The same phenomenon occurs with a proton
space. beam, neutron beam, and other beams of matter.
cosmology The study of the origin, structure, and evolution of double-slit experiment with light When single-frequency light
the large-scale universe. from two synchronized sources such as two narrow slits strikes a
coulomb Abbreviated “C.” The metric measurement unit for viewing screen, an interference pattern is observed. This demon-
electric charge. It’s the amount of charge that causes an electric strates that light is a wave.
force of 9 * 109 Non an identical charge at a distance of 1 m. It doubling time See exponential growth.
turns out to be the charge on 6.25 * 1018electrons. d-quark See strong force.
Coulomb’s law of the electric force Between any two small drift velocity The average forward speed of a typical electron
charged objects there is a force that is repulsive if both objects along a wire in an electric current, typically less than 1 mm/s.
have positive charge or if both have negative charge, and is attrac- dualism Descartes’ idea that there are two realities, physical
tive if one has positive and the other has negative charge. This and spiritual. In the physical realm, the real or primary qualities
force is proportional to the amount of charge on each object, and are objective, impersonal phenomena such as the motion of
proportional to the inverse of the square of the distance between atoms. Human sense impressions are considered to be secondary
them. In symbols it is F r q q d2. If charge is measured in qualities, caused by the primary qualities.
1 2>
coulombs and distance in meters, then the force in newtons is
given by F = 9 * 109 q1q2>d2. E = mc2 See principle of mass-energy equivalence.
creation and annihilation See antiparticle. efficiency See transportation efficiency, heat engine, and
creationism The belief that the Bible’s Old Testament can be energy efficiency.
read literally as scientific and historical truth and that Earth and elastic energy Energy due to the ability of a deformed system
the biological organisms, including humans, were created sepa- to snap back.
rately just a few thousand years ago. Scientists overwhelmingly electric circuit A closed loop around which electric current
reject creationism as pseudoscientific and false. canflow.
critical mass The minimum amount of fissionable material that electric charge See electrically charged object.
will sustain a chain reaction. electric current A flow or motion of electrically charged parti-
curved space See gravity and warped space. cles. Electric currents in wires are due to electrons moving along
the wire.
dark energy Observations show that the universe is filled with a electric discharge See excite.
nonmaterial form of energy that pushes outward on the fabric of electric (or electromagnetic) energy The energy that an
space, causing it to accelerate in its outward expansion. The proper- electrically charged object has due to its position in an electro-
ties and the cause of this energy are not understood. It comprises magnetic field.
73% of the energy (and therefore 73% of the mass) of the universe. electric field Exists wherever a charged object would feel an
dark matter Also known as “exotic dark matter,” this is matter electric force if such an object were present.
that does not interact with electromagnetic radiation and so does electric force The electric part of the electromagnetic force. See
not emit, absorb, or reflect light. It is made of entirely new and also electromagnetic force.
unknown forms of matter. Dark matter comprises 23% of the uni- electric force law Electrically charged objects exert forces on
verse’s mass (and therefore 23% of its energy), while other forms each other at a distance. Like charges repel each other, and unlike
of matter (stars, planets, gas, black holes, neutrinos) comprise 4%. charges attract each other.
daughter nucleus The nucleus that remains after a radioactive electric force law (field version) An electric field surrounds
decay has occurred. every charged object. Charged objects feel electric forces when-
DC See direct current. ever they are placed in an electric field.
decarbonization Replacement of high-carbon fossil fuels such electric generator See steam-electric power plant.
as coal with lower-carbon fuels such as natural gas, and with electric vehicle (EV) Vehicle powered by a storage battery that is
zero-carbon fuels such as solar energy, nuclear power, and hydro- recharged by plugging into a wall socket. Nonpolluting, provided
gen gas generated from nonfossil energy. that the electricity comes from an environmentally friendly source.
decay curve A graph of the amount of a radioactive material electrical conductor A material (usually a metal) through which
remaining, versus time. electric current can easily flow. The atoms of these materials have
degrees Celsius See temperature. one or two outermost electrons that are only loosely attached.
destructive interference See interference. electrical insulator A material that doesn’t permit the easy flow
difficulties with Aristotelian physics See Aristotelian physics, of electric current. The atoms of these materials have firmly
difficulties. attached outermost electrons.
direct current An electric current that maintains the same electrical resistance See resistance.
direction. electrically charged (in quantum electrodynamics) See
dirty bomb A bomb powered with conventional explosions that quantum electrodynamics.
does its damage primarily by the dispersal of radioactive materi- electrically charged object Any object that can exert or feel the
als. One of the possible forms of nuclear terrorism. electric force is said to “contain electric charge.” There are two
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