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Physics

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PhysicsShort Answer
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Table of contents
  1. Preface
  2. 1 What is Physics?
    1. Introduction
    2. 1.1 Physics: Definitions and Applications
    3. 1.2 The Scientific Methods
    4. 1.3 The Language of Physics: Physical Quantities and Units
    5. Key Terms
    6. Section Summary
    7. Key Equations
    8. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    9. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  3. 2 Motion in One Dimension
    1. Introduction
    2. 2.1 Relative Motion, Distance, and Displacement
    3. 2.2 Speed and Velocity
    4. 2.3 Position vs. Time Graphs
    5. 2.4 Velocity vs. Time Graphs
    6. Key Terms
    7. Section Summary
    8. Key Equations
    9. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    10. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  4. 3 Acceleration
    1. Introduction
    2. 3.1 Acceleration
    3. 3.2 Representing Acceleration with Equations and Graphs
    4. Key Terms
    5. Section Summary
    6. Key Equations
    7. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    8. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  5. 4 Forces and Newton’s Laws of Motion
    1. Introduction
    2. 4.1 Force
    3. 4.2 Newton's First Law of Motion: Inertia
    4. 4.3 Newton's Second Law of Motion
    5. 4.4 Newton's Third Law of Motion
    6. Key Terms
    7. Section Summary
    8. Key Equations
    9. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    10. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  6. 5 Motion in Two Dimensions
    1. Introduction
    2. 5.1 Vector Addition and Subtraction: Graphical Methods
    3. 5.2 Vector Addition and Subtraction: Analytical Methods
    4. 5.3 Projectile Motion
    5. 5.4 Inclined Planes
    6. 5.5 Simple Harmonic Motion
    7. Key Terms
    8. Section Summary
    9. Key Equations
    10. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    11. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  7. 6 Circular and Rotational Motion
    1. Introduction
    2. 6.1 Angle of Rotation and Angular Velocity
    3. 6.2 Uniform Circular Motion
    4. 6.3 Rotational Motion
    5. Key Terms
    6. Section Summary
    7. Key Equations
    8. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    9. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  8. 7 Newton's Law of Gravitation
    1. Introduction
    2. 7.1 Kepler's Laws of Planetary Motion
    3. 7.2 Newton's Law of Universal Gravitation and Einstein's Theory of General Relativity
    4. Key Terms
    5. Section Summary
    6. Key Equations
    7. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    8. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  9. 8 Momentum
    1. Introduction
    2. 8.1 Linear Momentum, Force, and Impulse
    3. 8.2 Conservation of Momentum
    4. 8.3 Elastic and Inelastic Collisions
    5. Key Terms
    6. Section Summary
    7. Key Equations
    8. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    9. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  10. 9 Work, Energy, and Simple Machines
    1. Introduction
    2. 9.1 Work, Power, and the Work–Energy Theorem
    3. 9.2 Mechanical Energy and Conservation of Energy
    4. 9.3 Simple Machines
    5. Key Terms
    6. Section Summary
    7. Key Equations
    8. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    9. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  11. 10 Special Relativity
    1. Introduction
    2. 10.1 Postulates of Special Relativity
    3. 10.2 Consequences of Special Relativity
    4. Key Terms
    5. Section Summary
    6. Key Equations
    7. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    8. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  12. 11 Thermal Energy, Heat, and Work
    1. Introduction
    2. 11.1 Temperature and Thermal Energy
    3. 11.2 Heat, Specific Heat, and Heat Transfer
    4. 11.3 Phase Change and Latent Heat
    5. Key Terms
    6. Section Summary
    7. Key Equations
    8. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    9. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  13. 12 Thermodynamics
    1. Introduction
    2. 12.1 Zeroth Law of Thermodynamics: Thermal Equilibrium
    3. 12.2 First law of Thermodynamics: Thermal Energy and Work
    4. 12.3 Second Law of Thermodynamics: Entropy
    5. 12.4 Applications of Thermodynamics: Heat Engines, Heat Pumps, and Refrigerators
    6. Key Terms
    7. Section Summary
    8. Key Equations
    9. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    10. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  14. 13 Waves and Their Properties
    1. Introduction
    2. 13.1 Types of Waves
    3. 13.2 Wave Properties: Speed, Amplitude, Frequency, and Period
    4. 13.3 Wave Interaction: Superposition and Interference
    5. Key Terms
    6. Section Summary
    7. Key Equations
    8. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    9. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  15. 14 Sound
    1. Introduction
    2. 14.1 Speed of Sound, Frequency, and Wavelength
    3. 14.2 Sound Intensity and Sound Level
    4. 14.3 Doppler Effect and Sonic Booms
    5. 14.4 Sound Interference and Resonance
    6. Key Terms
    7. Section Summary
    8. Key Equations
    9. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    10. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  16. 15 Light
    1. Introduction
    2. 15.1 The Electromagnetic Spectrum
    3. 15.2 The Behavior of Electromagnetic Radiation
    4. Key Terms
    5. Section Summary
    6. Key Equations
    7. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    8. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  17. 16 Mirrors and Lenses
    1. Introduction
    2. 16.1 Reflection
    3. 16.2 Refraction
    4. 16.3 Lenses
    5. Key Terms
    6. Section Summary
    7. Key Equations
    8. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    9. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  18. 17 Diffraction and Interference
    1. Introduction
    2. 17.1 Understanding Diffraction and Interference
    3. 17.2 Applications of Diffraction, Interference, and Coherence
    4. Key Terms
    5. Section Summary
    6. Key Equations
    7. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    8. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  19. 18 Static Electricity
    1. Introduction
    2. 18.1 Electrical Charges, Conservation of Charge, and Transfer of Charge
    3. 18.2 Coulomb's law
    4. 18.3 Electric Field
    5. 18.4 Electric Potential
    6. 18.5 Capacitors and Dielectrics
    7. Key Terms
    8. Section Summary
    9. Key Equations
    10. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    11. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  20. 19 Electrical Circuits
    1. Introduction
    2. 19.1 Ohm's law
    3. 19.2 Series Circuits
    4. 19.3 Parallel Circuits
    5. 19.4 Electric Power
    6. Key Terms
    7. Section Summary
    8. Key Equations
    9. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    10. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  21. 20 Magnetism
    1. Introduction
    2. 20.1 Magnetic Fields, Field Lines, and Force
    3. 20.2 Motors, Generators, and Transformers
    4. 20.3 Electromagnetic Induction
    5. Key Terms
    6. Section Summary
    7. Key Equations
    8. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    9. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  22. 21 The Quantum Nature of Light
    1. Introduction
    2. 21.1 Planck and Quantum Nature of Light
    3. 21.2 Einstein and the Photoelectric Effect
    4. 21.3 The Dual Nature of Light
    5. Key Terms
    6. Section Summary
    7. Key Equations
    8. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Problems
      4. Performance Task
    9. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  23. 22 The Atom
    1. Introduction
    2. 22.1 The Structure of the Atom
    3. 22.2 Nuclear Forces and Radioactivity
    4. 22.3 Half Life and Radiometric Dating
    5. 22.4 Nuclear Fission and Fusion
    6. 22.5 Medical Applications of Radioactivity: Diagnostic Imaging and Radiation
    7. Key Terms
    8. Section Summary
    9. Key Equations
    10. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Performance Task
    11. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  24. 23 Particle Physics
    1. Introduction
    2. 23.1 The Four Fundamental Forces
    3. 23.2 Quarks
    4. 23.3 The Unification of Forces
    5. Key Terms
    6. Section Summary
    7. Chapter Review
      1. Concept Items
      2. Critical Thinking Items
      3. Performance Task
    8. Test Prep
      1. Multiple Choice
      2. Short Answer
      3. Extended Response
  25. A | Reference Tables
  26. Index

Short Answer

21.1 Planck and Quantum Nature of Light

46 .
Describe the form of a blackbody radiation curve if all frequencies of light were emitted with equal probability.
  1. The curve would appear as a Gaussian probability distribution with a large peak in the middle.
  2. The curve would appear as a vertical line.
  3. The curve would appear as a horizontal line.
  4. The curve would appear as a diagonal line correlating intensity to frequency at a 1:1 ratio.
47.

Because there are more gradations to high frequency radiation than low frequency radiation, scientists also thought it possible that a curve titled the ultraviolet catastrophe would occur. Explain what the blackbody radiation curve would look like if this were the case.

  1. The curve would steadily increase in intensity with increasing frequency.
  2. The curve would steadily decrease in intensity with increasing frequency.
  3. The curve would be much steeper than in the blackbody radiation graph.
  4. The curve would be much flatter than in the blackbody radiation graph.
48.

Energy provided by a light exists in the following quantities: 150 J, 225 J, 300 J. Define one possible quantum of energy and provide an energy state that cannot exist with this quantum.

  1. 65 J; 450 J cannot exist
  2. 70 J; 450 J cannot exist
  3. 75 J; 375 J cannot exist
  4. 75 J; 100 J cannot exist
49 .
How did Planck’s work come to be regarded as a major dividing line between classical and modern physics?
  1. Planck’s constant is smaller than any previous discovered constant.
  2. Planck hypothesized that energy is quantized rather than continuous.
  3. Planck’s theories meant that classical physics was no longer useful for any system.
  4. Plank discovered the blackbody radiation spectrum.
50.

How many 500-mm microwave photons are needed to supply the 8 kJ of energy necessary to heat a cup of water by 10 degrees Celsius?

  1. 8.05 × 1028 photons
  2. 8.05 × 1026 photons
  3. 2.01 × 1026 photons
  4. 2.01 × 1028 photons
51.

What is the efficiency of a 100-W, 550-nm lightbulb if a photometer finds that 1 × 1020 photons are emitted each second?

  1. 101 percent
  2. 72 percent
  3. 18 percent
  4. 36 percent
52 .
Which form of electromagnetic radiation would deliver the most photons per unit time from a distant galaxy to an observer on Earth?
  1. Gamma rays
  2. Radio waves
  3. Ultraviolet light
  4. X-rays
53 .
Why are photons of gamma rays and X-rays able to penetrate objects more successfully than ultraviolet radiation?
  1. Photons of gamma rays and X-rays carry with them less energy.
  2. Photons of gamma rays and X-rays have longer wavelengths.
  3. Photons of gamma rays and X-rays have lower frequencies.
  4. Photons of gamma rays and X-rays carry with them more energy.

21.2 Einstein and the Photoelectric Effect

54.

According to wave theory, what is necessary to eject electrons from a surface?

  1. Enough energy to overcome the binding energy of the electrons at the surface
  2. A frequency that is higher than that of the electrons at the surface
  3. Energy that is lower than the binding energy of the electrons at the surface
  4. A very small number of photons
55.

What is the wavelength of EM radiation that ejects 2.00-eV electrons from calcium metal, given that the binding energy is 2.71 eV?

  1. 16.1 × 105 m
  2. 6.21 × 10−5 m
  3. 9.94 × 10−26 m
  4. 2.63 × 10-7 m
56 .
Find the wavelength of photons that eject 0.100 -eV electrons from potassium, given that the binding energy is 2.24 eV .
  1. 6.22 × 10 − 7 m
  2. 5.92 × 10 − 5 m
  3. 1.24 × 10 − 5 m
  4. 5.31 × 10 − 7 m
57 .
An extremely efficient solar panel is designed with an energy gap of 1.4 eV. If shining a light on the panel causes a current to flow and the temperature of the panel to increase slightly, what can you say about the wavelength of the light?
  1. The light’s wavelength was about 837 nm.
  2. The light’s wavelength was about 886 nm.
  3. The light’s wavelength was about 908 nm.
  4. The light’s wavelength was about 950 nm.
58 .
How do solar panels work?
  1. Solar panels take advantage of the photoelectric effect to store potential energy as heat.
  2. Solar panels take advantage of the photoelectric effect to convert heat energy into power.
  3. Solar panels take advantage of the photoelectric effect to generate power from incoming radiation.
  4. Solar panels take advantage of the photoelectric effect to create light from incoming heat energy.

21.3 The Dual Nature of Light

59 .
Predict the effect on a photon’s wavelength of a collision with an electron.
  1. The photon’s wavelength will drop to zero.
  2. The photon’s wavelength will decrease.
  3. The photon’s wavelength will increase.
  4. The photon’s wavelength will be inverted.
60 .
Compare the momentums of a proton and an electron with the same energy and explain any difference.
  1. Their momentums are the same because they have the same energy.
  2. The electron has a greater momentum than the photon; photon momentum arises from Planck’s constant which is many orders of magnitude smaller than the mass of an electron.
  3. The photon has a greater momentum than the electron; photon momentum arises from the speed of light which is much faster than an electron can move.
  4. The photon must have a momentum of zero because its rest mass is zero.
61.

A 500-nm photon strikes an electron and loses 20 percent of its energy. What is the new momentum of the photon?

  1. 4.24 × 10−27 kg ⋅ m/s
  2. 3.18 × 10−27 kg ⋅ m/s
  3. 2.12 × 10−27 kg ⋅ m/s
  4. 1.06 × 10−27 kg ⋅ m/s
62.

A 500-nm photon strikes an electron and loses 20 percent of its energy. What is the speed of the recoiling electron?

  1. 7.18 × 105 m/s
  2. 6.18 × 105 m/s
  3. 5.18 × 105 m/s
  4. 4.18 × 105 m/s
63.

When a photon strikes a solar sail, what is the direction of impulse on the photon?

  1. parallel to the sail
  2. perpendicular to the sail
  3. tangential to the sail
  4. opposite to the sail
64 .
What is a fundamental difference between solar sails and sails that are used on sailboats?
  1. Solar sails rely on disorganized strikes from light particles, while sailboats rely on disorganized strikes from air particles.
  2. Solar sails rely on disorganized strikes from air particles, while sailboats rely on disorganized strikes from light particles.
  3. Solar sails rely on organized strikes from air particles, while sailboats rely on organized strikes from light particles.
  4. Solar sails rely on organized strikes from light particles, while sailboats rely on organized strikes from air particles.
65.

The wavelength of a particle is called the de Broglie wavelength, and it can be found with the equation p=hλp=hλ .
Yes or no—Can the wavelength of an electron match that of a proton?

  1. Yes, a slow-moving electron can achieve the same momentum as a slow-moving proton.
  2. No, a fast-moving electron cannot achieve the same momentum, and hence the same wavelength, as a proton.
  3. No, an electron can achieve the same momentum, and hence not the same wavelength, as a proton.
  4. Yes, a fast-moving electron can achieve the same momentum, and hence have the same wavelength, as a slow-moving proton.
66 .
Why do we not observe the wave-like nature of an object such as quickly rolling bowling ball?
  1. The length of the wave is the same as the diameter of the ball, so they are indistinguishable.
  2. The length of the wave is longer than the diameter of the ball, making the wave difficult to observe.
  3. The length of the wave is much shorter than the diameter of the ball, making the wave difficult to observe.
  4. The ball is not rolling quickly enough to have wave-like qualities.
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