Modern Physics for Scientists and Engineers 4th edition

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Stephen T. Thornton and Andrew Rex
Publisher: Cengage Learning


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  • Chapter 1: The Birth of Modern Physics
    • 1.1: Classical Physics of the 1890s
    • 1.2: The Kinetic Theory of Gases
    • 1.3: Waves and Particles
    • 1.4: Conservation Laws and Fundamental Forces
    • 1.5: The Atomic Theory of Matter
    • 1.6: Unresolved Questions of 1895 and New Horizons
    • 1: Supplemental Multiple Choice Questions (10)

  • Chapter 2: Special Theory of Relativity
    • 2.1: The Apparent Need for Ether
    • 2.2: The Michelson-Morley Experiment (2)
    • 2.3: Einstein's Postulates
    • 2.4: The Lorentz Transformation (5)
    • 2.5: Time Dilation and Length Contraction (4)
    • 2.6: Addition of Velocities (4)
    • 2.7: Experimental Verification
    • 2.8: Twin Paradox
    • 2.9: Spacetime
    • 2.10: Doppler Effect (2)
    • 2.11: Relativistic Momentum (3)
    • 2.12: Relativistic Energy (4)
    • 2.13: Computations in Modern Physics (2)
    • 2.14: Electromagnetism and Relativity
    • 2: General Problems (2)
    • 2: Questions
    • 2: Supplemental Multiple Choice Questions (10)

  • Chapter 3: The Experimental Basis of Quantum Physics
    • 3.1: Discovery of the X Ray and the Electron (2)
    • 3.2: Determination of Electron Charge (1)
    • 3.3: Line Spectra (3)
    • 3.4: Quantization
    • 3.5: Blackbody Radiation (4)
    • 3.6: Photoelectric Effect (5)
    • 3.7: X-Ray Production
    • 3.8: Compton Effect (3)
    • 3.9: Pair Production and Annihilation
    • 3: General Problems (1)
    • 3: Questions
    • 3: Supplemental Multiple Choice Questions (12)

  • Chapter 4: Structure of the Atom
    • 4.1: The Atomic Models of Thomson and Rutherford
    • 4.2: Rutherford Scattering (2)
    • 4.3: The Classical Atomic Model
    • 4.4: The Bohr Model of the Hydrogen Atom (4)
    • 4.5: Successes and Failures of the Bohr Model
    • 4.6: Characteristic X-Ray Spectra and Atomic Number (3)
    • 4.7: Atomic Excitation by Electrons (1)
    • 4: General Problems (3)
    • 4: Questions
    • 4: Supplemental Multiple Choice Questions (10)

  • Chapter 5: Wave Properties of Matter and Quantum Mechanics I
    • 5.1: X-Ray Scattering (3)
    • 5.2: De Broglie Waves (4)
    • 5.3: Electron Scattering (3)
    • 5.4: Wave Motion (2)
    • 5.5: Waves or Particles?
    • 5.6: Uncertainty Principle (4)
    • 5.7: Probability, Wave Functions, and the Copenhagen Interpretation (1)
    • 5.8: Particle in a Box
    • 5: General Problems (3)
    • 5: Questions
    • 5: Supplemental Multiple Choice Questions (11)

  • Chapter 6: Quantum Mechanics II
    • 6.1: The Schrödinger Wave Equation
    • 6.2: Expectation Values (1)
    • 6.3: Infinite Square-Well Potential (4)
    • 6.4: Finite Square-Well Potential (1)
    • 6.5: Three-Dimensional Infinite-Potential Well (1)
    • 6.6: Simple Harmonic Oscillator (4)
    • 6.7: Barriers and Tunneling (4)
    • 6: General Problems (2)
    • 6: Questions
    • 6: Supplemental Multiple Choice Questions (10)

  • Chapter 7: The Hydrogen Atom
    • 7.1: Application of the Schrödinger Equation to the Hydrogen Atom
    • 7.2: Solution of the Schrödinger Equation for Hydrogen (1)
    • 7.3: Quantum Numbers (4)
    • 7.4: Magnetic Effects on Atomic Spectra—The Normal Zeeman Effect (5)
    • 7.5: Intrinsic Spin (2)
    • 7.6: Energy Levels and Electron Probabilities (4)
    • 7: General Problems
    • 7: Questions
    • 7: Supplemental Multiple Choice Questions (10)

  • Chapter 8: Atomic Physics
    • 8.1: Atomic Structure and the Periodic Table (4)
    • 8.2: Total Angular Momentum (9)
    • 8.3: Anomalous Zeeman Effect (3)
    • 8: General Problems
    • 8: Questions
    • 8: Supplemental Multiple Choice Questions (10)

  • Chapter 9: Statistical Physics
    • 9.1: Historical Overview
    • 9.2: Maxwell Velocity Distribution
    • 9.3: Equipartition Theorem (1)
    • 9.4: Maxwell Speed Distribution (3)
    • 9.5: Classical and Quantum Statistics (1)
    • 9.6: Fermi-Dirac Statistics (3)
    • 9.7: Bose-Einstein Statistics (1)
    • 9: General Problems (3)
    • 9: Questions
    • 9: Supplemental Multiple Choice Questions (10)

  • Chapter 10: Molecules, Lasers, and Solids
    • 10.1: Molecular Bonding and Spectra (4)
    • 10.2: Stimulated Emission and Lasers (2)
    • 10.3: Structural Properties of Solids (1)
    • 10.4: Thermal and Magnetic Properties of Solids
    • 10.5: Superconductivity (3)
    • 10.6: Applications of Superconductivity (2)
    • 10: General Problems
    • 10: Questions
    • 10: Supplemental Multiple Choice Questions (10)

  • Chapter 11: Semiconductor Theory and Devices
    • 11.1: Band Theory of Solids
    • 11.2: Semiconductor Theory (5)
    • 11.3: Semiconductor Devices (2)
    • 11.4: Nanotechnology
    • 11: General Problems (5)
    • 11: Questions
    • 11: Supplemental Multiple Choice Questions (10)

  • Chapter 12: The Atomic Nucleus
    • 12.1: Discovery of the Neutron
    • 12.2: Nuclear Properties (2)
    • 12.3: The Deuteron
    • 12.4: Nuclear Forces (1)
    • 12.5: Nuclear Stability (2)
    • 12.6: Radioactive Decay (4)
    • 12.7: Alpha, Beta, and Gamma Decay (4)
    • 12.8: Radioactive Nuclides (4)
    • 12: General Problems
    • 12: Questions
    • 12: Supplemental Multiple Choice Questions (10)

  • Chapter 13: Nuclear Interactions and Applications
    • 13.1: Nuclear Reactions (3)
    • 13.2: Reaction Kinematics (5)
    • 13.3: Reaction Mechanisms (2)
    • 13.4: Fission (2)
    • 13.5: Fission Reactors (2)
    • 13.6: Fusion
    • 13.7: Special Applications (3)
    • 13: General Problems
    • 13: Questions
    • 13: Supplemental Multiple Choice Questions (10)

  • Chapter 14: Particle Physics
    • 14.1: Early Discoveries
    • 14.2: The Fundamental Interactions (1)
    • 14.3: Classification of Particles (1)
    • 14.4: Conservation Laws and Symmetries (4)
    • 14.5: Quarks (3)
    • 14.6: The Families of Matter
    • 14.7: Beyond the Standard Model (4)
    • 14.8: Accelerators (3)
    • 14: General Problems (2)
    • 14: Questions
    • 14: Supplemental Multiple Choice Questions (10)

  • Chapter 15: General Relativity
    • 15.1: Tenets of General Relativity
    • 15.2: Tests of General Relativity (3)
    • 15.3: Gravitational Waves
    • 15.4: Black Holes (2)
    • 15.5: Frame Dragging
    • 15: General Problems (3)
    • 15: Questions
    • 15: Supplemental Multiple Choice Questions (10)

  • Chapter 16: Cosmology and Modern Astrophysics—The Beginning and the End
    • 16.1: Evidence of the Big Bang
    • 16.2: The Big Bang (3)
    • 16.3: Stellar Evolution
    • 16.4: Astronomical Objects (4)
    • 16.5: Problems with the Big Bang (1)
    • 16.6: The Age of the Universe
    • 16.7: The Standard Model of Cosmology
    • 16.8: The Future
    • 16: General Problems (3)
    • 16: Questions
    • 16: Supplemental Multiple Choice Questions (10)


The 4th edition of Modern Physics for Scientists and Engineers by S. Thornton and A. Rex features WebAssign questions directly from the textbook with randomized variables, as well as supplementary multiple choice questions.

Questions Available within WebAssign

Most questions from this textbook are available in WebAssign. The online questions are identical to the textbook questions except for minor wording changes necessary for Web use. Whenever possible, variables, numbers, or words have been randomized so that each student receives a unique version of the question. This list is updated nightly.

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Group Quantity Questions
Chapter 1: The Birth of Modern Physics
1.SMC 10 001 002 003 004 005 006 007 008 009 010
Chapter 2: Special Theory of Relativity
2.P 28 004 006 012 013 014 016 017 020 021 026 027 031 033 034 035 051 054 058 059 060 066 067 070 078 082 083 095 098
2.SMC 10 001 002 003 004 005 006 007 008 009 010
Chapter 3: The Experimental Basis of Quantum Physics
3.P 19 003 004 008 009 010 011 017 018 019 026 033 034 036 037 039 047 052 053 056
3.SMC 12 001 002 003 004 005 006 007 008 009 010 011 012
Chapter 4: Structure of the Atom
4.P 13 006 008 024 029 031 032 041 042 043 045 049 050 051
4.SMC 10 001 002 003 004 005 006 007 008 009 010
Chapter 5: Wave Properties of Matter and Quantum Mechanics I
5.P 20 002 003 004 010 012 013 015 020 021 022 026 030 042 043 044 046 048 062 063 064
5.SMC 11 001 002 003 004 005 006 007 008 009 010 011
Chapter 6: Quantum Mechanics II
6.P 17 011 016 017 018 021 022 026 035 036 038 039 042 045 046 048 056 067
6.SMC 10 001 002 003 004 005 006 007 008 009 010
Chapter 7: The Hydrogen Atom
7.P 16 006 010 011 014 015 020 022 023 024 025 029 030 034 038 040 042
7.SMC 10 001 002 003 004 005 006 007 008 009 010
Chapter 8: Atomic Physics
8.P 16 004 007 008 009 012 015 016 018 020 022 024 025 026 030 033 037
8.SMC 10 001 002 003 004 005 006 007 008 009 010
Chapter 9: Statistical Physics
9.P 12 004 007 009 010 016 024 028 035 040 050 057 059
9.SMC 10 001 002 003 004 005 006 007 008 009 010
Chapter 10: Molecules, Lasers, and Solids
10.P 12 009 010 014 016 018 021 026 050 051 052 056 057
10.SMC 10 001 002 003 004 005 006 007 008 009 010
Chapter 11: Semiconductor Theory and Devices
11.P 12 001 002 004 005 008 014 015 019 020 022 028 033
11.SMC 10 001 002 003 004 005 006 007 008 009 010
Chapter 12: The Atomic Nucleus
12.P 17 008 010 016 017 018 027 028 033 034 039 042 043 045 049 052 053 054
12.SMC 10 001 002 003 004 005 006 007 008 009 010
Chapter 13: Nuclear Interactions and Applications
13.P 17 003 006 007 008 009 015 016 017 019 020 027 028 030 031 050 051 053
13.SMC 10 001 002 003 004 005 006 007 008 009 010
Chapter 14: Particle Physics
14.P 18 007 008 014 015 016 017 020 021 022 025 026 027 028 033 034 040 049 052
14.SMC 10 001 002 003 004 005 006 007 008 009 010
Chapter 15: General Relativity
15.P 8 006 007 009 012 015 021 023 025
15.SMC 10 001 002 003 004 005 006 007 008 009 010
Chapter 16: Cosmology and Modern Astrophysics—The Beginning and the End
16.P 11 003 006 009 014 015 016 019 021 025 035 038
16.SMC 10 001 002 003 004 005 006 007 008 009 010
Total 399