Question 1

What is the energy of a photon whose frequency is 2.9 × 1020 Hz? (h = 6.63 × 10−34 J⋅s and 1 eV = 1.60 × 10−19 J)

Accepted Answer

A)  0.2 MeV 
B)  1.2 MeV 
C)  1.9 MeV 
D)  3.1 MeV 
E)  ​0.8 MeV 
A)  0.2 MeV 
B)  1.2 MeV 
C)  1.9 MeV 
D)  3.1 MeV 
E)  ​0.8 MeV B

Question 2

What is the wavelength of a monochromatic light beam,where the photon energy is 2.15 eV? (h = 6.63 × 10−34 J⋅s,c = 3.00 × 108 m/s,1 nm = 10−9 m,and 1 eV = 1.6 × 10−19 J)

Accepted Answer

A)  308 nm 
B)  578 nm 
C)  223 nm 
D)  156 nm 
E)  ​475 nm 
A)  308 nm 
B)  578 nm 
C)  223 nm 
D)  156 nm 
E)  ​475 nm B

Question 3

Violet light (λ = 430 nm)is incident on a piece of potassium (φ = 2.20 eV).What is the maximum kinetic energy of the ejected photoelectrons? (h = 6.63 × 10−34 J⋅s,c = 3.00 × 108 m/s,1 eV = 1.60 × 10−19 J,and 1 nm = 10−9 m)

Accepted Answer

A)  2.43 eV 
B)  0.69 eV 
C)  2.89 eV 
D)  5.09 eV 
E)  ​0.96 eV 
A)  2.43 eV 
B)  0.69 eV 
C)  2.89 eV 
D)  5.09 eV 
E)  ​0.96 eV B

Question 4

A proton and an electron each have the same de Broglie wavelength.(i)Which has the greater speed,and (ii)which has the greater kinetic energy?

Accepted Answer

A)  (i)the electron,(ii)Either one can have the greater kinetic energy. 
B)  (i)the proton,(ii)Either one can have the greater kinetic energy. 
C)  (i)the electron,(ii)the electron 
D)  (i)the proton,(ii)the proton 
A)  (i)the electron,(ii)Either one can have the greater kinetic energy. 
B)  (i)the proton,(ii)Either one can have the greater kinetic energy. 
C)  (i)the electron,(ii)the electron 
D)  (i)the proton,(ii)the proton

Question 5

A photon absorbed by an electron will give up more energy to the electron if the photon:

Accepted Answer

A)  is not spread out over many electrons. 
B)  is moving faster. 
C)  is moving slower. 
D)  has a higher frequency. 
A)  is not spread out over many electrons. 
B)  is moving faster. 
C)  is moving slower. 
D)  has a higher frequency.

Question 6

In regard to the Compton scattering experiment with x-rays incident upon a carbon block,as the scattering angle becomes larger,what happens to the magnitude of difference between the incident and scattered wavelengths?

Accepted Answer

A)  increases 
B)  decreases 
C)  remains constant 
D)  difference is maximum at a 45° angle of scatter 
A)  increases 
B)  decreases 
C)  remains constant 
D)  difference is maximum at a 45° angle of scatter

Question 7

Which of the following devices represent(s)a practical application of the photoelectric effect?

Accepted Answer

A)  hologram 
B)  photocell 
C)  both of the above choices 
D)  none of the above choices 
A)  hologram 
B)  photocell 
C)  both of the above choices 
D)  none of the above choices

Question 8

Classical theories predict that most of the energy from a blackbody should be radiated:

Accepted Answer

A)  as thermal radiation in the infrared region. 
B)  at the wavelength given by Wien's displacement law. 
C)  as ultraviolet light. 
D)  a blackbody should not radiate. 
A)  as thermal radiation in the infrared region. 
B)  at the wavelength given by Wien's displacement law. 
C)  as ultraviolet light. 
D)  a blackbody should not radiate.

Question 9

According to de Broglie,as the momentum of a moving particle is tripled,the corresponding wavelength changes by what factor?

Accepted Answer

A)  1/9 
B)  1/3 
C)  3 
D)  9 
A)  1/9 
B)  1/3 
C)  3 
D)  9

Question 10

An important use of x-ray diffraction was:

Accepted Answer

A)  the observation of Compton scattering. 
B)  determining the structure of the DNA molecule. 
C)  production of positrons. 
D)  observation of the photoelectric effect. 
A)  the observation of Compton scattering. 
B)  determining the structure of the DNA molecule. 
C)  production of positrons. 
D)  observation of the photoelectric effect.

Question 11

What is the minimum x-ray wavelength produced when electrons are accelerated through a potential of 46,800 V? (h = 6.63 × 10−34 J⋅s,c = 3.00 × 108 m/s,and 1 eV = 1.60 × 10−19 J)

Accepted Answer

A)  4.25E-11 m 
B)  8.85E-12 m 
C)  4.01E-12 m 
D)  2.66E-11 m 
E)  ​6.80E-11 m 
A)  4.25E-11 m 
B)  8.85E-12 m 
C)  4.01E-12 m 
D)  2.66E-11 m 
E)  ​6.80E-11 m

Question 12

Which of the following statements best describes the relation between the quantum theory and the photoelectric effect experiment?

Accepted Answer

A)  Quantum theory explains the photoelectric effect. 
B)  The photoelectric effect contradicts quantum theory. 
C)  Quantum theory has no bearing on the photoelectric effect. 
D)  The photoelectric effect explains quantum theory. 
A)  Quantum theory explains the photoelectric effect. 
B)  The photoelectric effect contradicts quantum theory. 
C)  Quantum theory has no bearing on the photoelectric effect. 
D)  The photoelectric effect explains quantum theory.

Question 13

X-ray production occurs in which process?

Accepted Answer

A)  photons hitting a metal,emitting electrons 
B)  electrons hitting a metal,emitting photons 
C)  photons hitting a metal,emitting x-rays 
D)  electrons hitting a metal and scattering elastically 
A)  photons hitting a metal,emitting electrons 
B)  electrons hitting a metal,emitting photons 
C)  photons hitting a metal,emitting x-rays 
D)  electrons hitting a metal and scattering elastically

Question 14

Who conceived the idea of using a crystal for observing diffraction of x-rays?

Accepted Answer

A)  Roentgen 
B)  von Laue 
C)  W.L.Bragg 
D)  W.H.Bragg 
A)  Roentgen 
B)  von Laue 
C)  W.L.Bragg 
D)  W.H.Bragg

Question 15

X-rays of wavelength of 0.0656 nm undergo Compton scattering from free electrons in carbon.What is the wavelength of photons scattered at 82.5° relative to the incident beam? (h = 6.63 × 10−34 J⋅s,me = 9.11 × 10−31 kg,c = 3.00 × 108 m/s,and 1 nm = 10−9 m)

Accepted Answer

A)  0.0656 nm 
B)  0.0677 nm 
C)  0.0848 nm 
D)  0.0719 nm 
E)  ​0.0659 nm 
A)  0.0656 nm 
B)  0.0677 nm 
C)  0.0848 nm 
D)  0.0719 nm 
E)  ​0.0659 nm

Question 16

A monochromatic light beam is incident on a barium target,which has a work function of 2.6 eV.If a stopping potential of 1.2 V is required,what is the light beam photon energy?

Accepted Answer

A)  2.6 eV 
B)  1.4 eV 
C)  1.2 eV 
D)  3.8 eV 
E)  ​0.7 
A)  2.6 eV 
B)  1.4 eV 
C)  1.2 eV 
D)  3.8 eV 
E)  ​0.7

Question 17

If a monochromatic light beam with quantum energy value of 1.6 eV incident upon a photocell where the work function of the target metal is 0.9 eV,what is the maximum kinetic energy of ejected electrons?

Accepted Answer

A)  2.5 eV 
B)  1.8 eV 
C)  0.7 eV 
D)  3.2 eV 
E)  ​1.3 eV 
A)  2.5 eV 
B)  1.8 eV 
C)  0.7 eV 
D)  3.2 eV 
E)  ​1.3 eV

Question 18

Which process cannot occur if only one photon is involved?

Accepted Answer

A)  Compton effect 
B)  pair production 
C)  the photoelectric effect 
D)  x-ray production 
A)  Compton effect 
B)  pair production 
C)  the photoelectric effect 
D)  x-ray production

Question 19

As the temperature of a radiation emitting blackbody becomes higher,what happens to the peak wavelength of the radiation?

Accepted Answer

A)  increases 
B)  decreases 
C)  remains constant 
D)  is directly proportional to temperature 
A)  increases 
B)  decreases 
C)  remains constant 
D)  is directly proportional to temperature

Question 20

An electron microscope operates with electrons of kinetic energy 58 keV.What is the wavelength of these electrons? Assume this speed is not relativistic.(h = 6.63 × 10−34 J⋅s,c = 3.00 × 108 m/s,1 eV = 1.60 × 10−19 J,and me = 9.11 × 10−31 kg)

Accepted Answer

A)  3.57E-20 m 
B)  7.69E-13 m 
C)  5.10E-12 m 
D)  2.28E-10 m 
E)  ​1.03E-11 m 
A)  3.57E-20 m 
B)  7.69E-13 m 
C)  5.10E-12 m 
D)  2.28E-10 m 
E)  ​1.03E-11 m

Exam 27: Quantum Physics Blackbody Radiation and Plancks Hypothesis

What is the energy of a photon whose frequency is 2.9 × 1020 Hz? (h = 6.63 × 10−34 J⋅s and 1 eV = 1.60 × 10−19 J)

What is the wavelength of a monochromatic light beam,where the photon energy is 2.15 eV? (h = 6.63 × 10−34 J⋅s,c = 3.00 × 108 m/s,1 nm = 10−9 m,and 1 eV = 1.6 × 10−19 J)

Violet light (λ = 430 nm)is incident on a piece of potassium (φ = 2.20 eV).What is the maximum kinetic energy of the ejected photoelectrons? (h = 6.63 × 10−34 J⋅s,c = 3.00 × 108 m/s,1 eV = 1.60 × 10−19 J,and 1 nm = 10−9 m)

A proton and an electron each have the same de Broglie wavelength.(i)Which has the greater speed,and (ii)which has the greater kinetic energy?

A photon absorbed by an electron will give up more energy to the electron if the photon:

In regard to the Compton scattering experiment with x-rays incident upon a carbon block,as the scattering angle becomes larger,what happens to the magnitude of difference between the incident and scattered wavelengths?

Which of the following devices represent(s)a practical application of the photoelectric effect?

Classical theories predict that most of the energy from a blackbody should be radiated:

According to de Broglie,as the momentum of a moving particle is tripled,the corresponding wavelength changes by what factor?

An important use of x-ray diffraction was:

What is the minimum x-ray wavelength produced when electrons are accelerated through a potential of 46,800 V? (h = 6.63 × 10−34 J⋅s,c = 3.00 × 108 m/s,and 1 eV = 1.60 × 10−19 J)

Which of the following statements best describes the relation between the quantum theory and the photoelectric effect experiment?

X-ray production occurs in which process?

Who conceived the idea of using a crystal for observing diffraction of x-rays?

X-rays of wavelength of 0.0656 nm undergo Compton scattering from free electrons in carbon.What is the wavelength of photons scattered at 82.5° relative to the incident beam? (h = 6.63 × 10−34 J⋅s,me = 9.11 × 10−31 kg,c = 3.00 × 108 m/s,and 1 nm = 10−9 m)

A monochromatic light beam is incident on a barium target,which has a work function of 2.6 eV.If a stopping potential of 1.2 V is required,what is the light beam photon energy?

If a monochromatic light beam with quantum energy value of 1.6 eV incident upon a photocell where the work function of the target metal is 0.9 eV,what is the maximum kinetic energy of ejected electrons?

Which process cannot occur if only one photon is involved?

As the temperature of a radiation emitting blackbody becomes higher,what happens to the peak wavelength of the radiation?

An electron microscope operates with electrons of kinetic energy 58 keV.What is the wavelength of these electrons? Assume this speed is not relativistic.(h = 6.63 × 10−34 J⋅s,c = 3.00 × 108 m/s,1 eV = 1.60 × 10−19 J,and me = 9.11 × 10−31 kg)

Introduction

Introduction: Part A

Motion in One Dimension

Motion in One Dimension: Part A

Vectors and Two-Dimensional Motion

Vectors and Two-Dimensional Motion: Part A

The Laws of Motion

The Laws of Motion: Part A

Energy

Energy: Part A

Momentum and Collisions

Momentum and Collisions: Part A

Rotational Motion and the Law of Gravity

Rotational Motion and the Law of Gravity: Part A

Rotational Equilibrium and Rotational Dynamics

Rotational Equilibrium and Rotational Dynamics: Part A

Solids and Fluids

Solids and Fluids: Part A

Thermal Physics

Thermal Physics: Part A

Energy in Thermal Processes Heat and Internal Energy

Energy in Thermal Processes Heat and Internal Energy: Part A

The Laws of Thermodynamics Work in Thermodynamic Processes

The Laws of Thermodynamics Work in Thermodynamic Processes: Part A

Vibrations and Waves

Vibrations and Waves: Part A

Sound

Sound: Part A

Electric Forces and Electric Fields

Electric Forces and Electric Fields: Part A

Electrical Energy and Capacitance

Electrical Energy and Capacitance: Part A

Current and Resistance Electric Current

Current and Resistance Electric Current: Part A

Direct-Current Circuits Sources of EMF

Direct-Current Circuits Sources of EMF: Part A

Magnetism Magnets

Magnetism Magnets: Part A

Induced Voltages and Inductance

Induced Voltages and Inductance: Part A

Alternating-Current Circuits and Electromagnetic Waves

Alternating-Current Circuits and Electromagnetic Waves: Part A

Reflection and Refraction of Light

Reflection and Refraction of Light: Part A

Mirrors and Lenses

Mirrors and Lenses: Part A

Wave Optics

Wave Optics: Part A

Optical Instruments

Optical Instruments: Part A

Relativity

Relativity: Part A

Quantum Physics Blackbody Radiation and Plancks Hypothesis: Part A

Atomic Physics

Atomic Physics: Part A

Nuclear Physics

Nuclear Physics: Part A

Nuclear Energy and Elementary Particles

Nuclear Energy and Elementary Particles: Part A

What is the energy of a photon whose frequency is 2.9 × 10²⁰ Hz? (h = 6.63 × 10−³⁴ J⋅s and 1 eV = 1.60 × 10−¹⁹ J)

What is the wavelength of a monochromatic light beam,where the photon energy is 2.15 eV? (h = 6.63 × 10−³⁴ J⋅s,c = 3.00 × 10⁸ m/s,1 nm = 10−⁹ m,and 1 eV = 1.6 × 10−¹⁹ J)

Violet light (λ = 430 nm)is incident on a piece of potassium (φ = 2.20 eV).What is the maximum kinetic energy of the ejected photoelectrons? (h = 6.63 × 10−³⁴ J⋅s,c = 3.00 × 10⁸ m/s,1 eV = 1.60 × 10−¹⁹ J,and 1 nm = 10−⁹ m)

What is the minimum x-ray wavelength produced when electrons are accelerated through a potential of 46,800 V? (h = 6.63 × 10−³⁴ J⋅s,c = 3.00 × 10⁸ m/s,and 1 eV = 1.60 × 10−¹⁹ J)

X-rays of wavelength of 0.0656 nm undergo Compton scattering from free electrons in carbon.What is the wavelength of photons scattered at 82.5° relative to the incident beam? (h = 6.63 × 10−³⁴ J⋅s,m_e = 9.11 × 10−³¹ kg,c = 3.00 × 10⁸ m/s,and 1 nm = 10−⁹ m)

An electron microscope operates with electrons of kinetic energy 58 keV.What is the wavelength of these electrons? Assume this speed is not relativistic.(h = 6.63 × 10−³⁴ J⋅s,c = 3.00 × 10⁸ m/s,1 eV = 1.60 × 10−¹⁹ J,and m_e = 9.11 × 10−³¹ kg)