Question 1

In the Bohr model of the hydrogen atom, the stationary states are circular orbits in which what property of the electron is quantized in integral multiples of h/2π?

Accepted Answer

A)   kinetic energy
B)   potential energy
C)   total energy
D)   linear momentum
E)   angular momentumF) C) and E)
G) A) and D)

Question 2

Electrons are used to produce x-rays by allowing a beam of electrons to strike a heavy metal surface. When the intensity of the electron beam is increased, this produces

Accepted Answer

A)   x-rays with longer wavelengths.
B)   x-rays with higher energy.
C)   more x-rays per unit time.
D)   faster x-rays.E) C) and D)
F) B) and C)

Question 3

An x-ray photon with wavelength 15.0 pm is scattered through 84.0° by an electron. What is the resulting kinetic energy of the electron?

Accepted Answer

A)   568 keV
B)   59.5 keV
C)   30.1 keV
D)   15.0 keV
E)   10.5 keVF) D) and E)
G) All of the above

Question 4

What is the threshold frequency for a surface with work function 4.14 eV?

Accepted Answer

A)   1.00 × 1012 Hz
B)   1.00 × 1013 Hz
C)   1.00 × 1014 Hz
D)   1.00 × 1015 Hz
E)   1.00 × 1016 HzF) B) and D)
G) A) and B)

Question 5

A photon of frequency 6.40 × 1014 Hz has what energy?

Accepted Answer

A)   1.26 eV
B)   1.93 eV
C)   2.11 eV
D)   2.65 eV
E)   3.17 eVF) B) and D)
G) D) and E)

Question 6

The minimum energy that a photon must have to create an electron-positron pair is

Accepted Answer

A)   0.511 MeV.
B)   1.022 MeV.
C)   2.044 MeV.
D)   0.256 MeV.
E)   any amount more than zero.F) A) and E)
G) A) and B)

Question 7

What is the energy of a photon emitted in a transition from the n = 3 state to the n = 2 state in He+?

Accepted Answer

A)   15.1 eV
B)   7.56 eV
C)   3.78 eV
D)   2.12 eV
E)   1.89 eVF) A) and B)
G) A) and C)

Question 8

A laser beam emits 2.5 × 1020 photons per second with a wavelength of 663 nm. What is the power output of this laser?

Accepted Answer

A)   51 mW
B)   67 mW
C)   51 W
D)   75 W
E)   93 WF) A) and E)
G) B) and E)

Question 9

Electrons are used to produce x-rays by allowing a beam of electrons to strike a heavy metal surface. What is true about the wavelengths of the characteristic x-rays that are produced in such a situation?

Accepted Answer

A)   There is a continuous range of wavelengths produced, up to a maximum that depends on the energy of the electron beam used.
B)   There is a single wavelength of x-ray produced that depends on the energy of the electron beam used.
C)   There are a few specific wavelengths that are produced for a given metal and their wavelengths are independent of the energy of the electron beam used.
D)   There is a continuous range of wavelengths produced, down to a minimum that depends on the energy of the electron beam used.E) A) and B)
F) None of the above

Question 10

Photons from a source each have energy 3.30 eV. Photons from a second source have twice the frequency as those from the first source. What is the energy of a photon from the second source?

Accepted Answer

A)   6.60 eV
B)   13.2 eV
C)   1.65 eV
D)   0.825 eV
E)   3.30 eVF) B) and D)
G) B) and C)

Question 11

Electrons are accelerated through a potential difference of 90.0 kV and directed at a tungsten target to produce x-rays. What is the shortest wavelength of the x-rays produced?

Accepted Answer

A)   669 pm
B)   508 pm
C)   72.6 pm
D)   13.8 pm
E)   14.3 pmF) A) and B)
G) None of the above

Question 12

An x-ray photon with wavelength 15.0 pm is scattered at 84.0° by an electron. What is the wavelength of the scattered photon?

Accepted Answer

A)   31.0 pm
B)   14.9 pm
C)   1.57 pm
D)   17.2 pm
E)   12.8 pmF) A) and D)
G) All of the above

Question 13

The energy of a photon of wavelength 400 nm is

Accepted Answer

A)   3.11 × 10-19 J
B)   3.50 × 10-19 J
C)   3.87 × 10-19 J
D)   4.25 × 10-19 J
E)   4.97 × 10-19 JF) A) and C)
G) All of the above

Question 14

A photon that is emitted during a transition in hydrogen from the n = 27 state to the n = 2 state is in which of the following series?

Accepted Answer

A)   Lyman
B)   Balmer
C)   Paschen
D)   Brackett
E)   All of these choices are correct.F) A) and C)
G) A) and E)

Question 15

In a Compton scattering experiment, the scattered photon has a wavelength of 6.55 pm. If the scattering angle is 50°, what is the energy of the incident photon?

Accepted Answer

A)   1.43 MeV
B)   218 keV
C)   380 keV
D)   117 keV
E)   66.3 keVF) All of the above
G) B) and E)

Question 16

An electron passing close to a target nucleus slows and radiates away some of its energy. What is the process called?

Accepted Answer

A)   blackbody radiation
B)   photoelectric effect
C)   stimulated emission
D)   bremsstrahlung
E)   Compton scatteringF) C) and E)
G) A) and E)

Question 17

What is the radius of the ground state of He+?

Accepted Answer

A)   0.0529 nm
B)   0.193 nm
C)   0.0265 nm
D)   0.106 nm
E)   0.212 nmF) All of the above
G) B) and E)

Question 18

In a Compton scattering experiment, the scattered photon has a wavelength of 6.55 pm. If the scattering angle is 50°, what was the wavelength of the incident photon?

Accepted Answer

A)   5.68 pm
B)   7.42 pm
C)   3.28 pm
D)   0.868 pm
E)   2.43 pmF) A) and D)
G) A) and C)

Question 19

A photocell is a device that operates using the photoelectric effect. What metal would enable a photocell to be operated using visible light?

Accepted Answer

A)   manganese (φ = 4.1 eV) 
B)   lanthanum (φ = 3.5 eV) 
C)   cesium (φ = 1.95 eV) 
D)   beryllium (φ = 4.98 eV) E) A) and B)
F) B) and C)

Question 20

What is the wavelength of the photon emitted when a hydrogen atom makes a transition from the n = 4 state to the n = 1 state?

Accepted Answer

A)   323 nm
B)   156 nm
C)   121 nm
D)   103 nm
E)   97.3 nmF) B) and D)
G) C) and D)

Exam 27: Early Quantum Physics and the Photon

Electrons are accelerated through a potential difference of 90.0 kV and directed at a tungsten target to produce x-rays. What is the shortest wavelength of the x-rays produced?

Correct AnswerverifiedShow Answer

What is the radius of the ground state of He+?

Correct AnswerverifiedShow Answer

The minimum energy that a photon must have to create an electron-positron pair is

Correct AnswerverifiedShow Answer

Electrons are used to produce x-rays by allowing a beam of electrons to strike a heavy metal surface. When the intensity of the electron beam is increased, this produces

Correct AnswerverifiedShow Answer

Electrons are used to produce x-rays by allowing a beam of electrons to strike a heavy metal surface. What is true about the wavelengths of the characteristic x-rays that are produced in such a situation?

Correct AnswerverifiedShow Answer

An electron passing close to a target nucleus slows and radiates away some of its energy. What is the process called?

Correct AnswerverifiedShow Answer

A laser beam emits 2.5 × 1020 photons per second with a wavelength of 663 nm. What is the power output of this laser?

Correct AnswerverifiedShow Answer

What is the threshold frequency for a surface with work function 4.14 eV?

Correct AnswerverifiedShow Answer

In a Compton scattering experiment, the scattered photon has a wavelength of 6.55 pm. If the scattering angle is 50°, what was the wavelength of the incident photon?

Correct AnswerverifiedShow Answer

Photons from a source each have energy 3.30 eV. Photons from a second source have twice the frequency as those from the first source. What is the energy of a photon from the second source?

Correct AnswerverifiedShow Answer

An x-ray photon with wavelength 15.0 pm is scattered at 84.0° by an electron. What is the wavelength of the scattered photon?

Correct AnswerverifiedShow Answer

A photon that is emitted during a transition in hydrogen from the n = 27 state to the n = 2 state is in which of the following series?

Correct AnswerverifiedShow Answer

In the Bohr model of the hydrogen atom, the stationary states are circular orbits in which what property of the electron is quantized in integral multiples of h/2π?

Correct AnswerverifiedShow Answer

In a Compton scattering experiment, the scattered photon has a wavelength of 6.55 pm. If the scattering angle is 50°, what is the energy of the incident photon?

Correct AnswerverifiedShow Answer

What is the energy of a photon emitted in a transition from the n = 3 state to the n = 2 state in He+?

Correct AnswerverifiedShow Answer

A photocell is a device that operates using the photoelectric effect. What metal would enable a photocell to be operated using visible light?

Correct AnswerverifiedShow Answer

A photon of frequency 6.40 × 1014 Hz has what energy?

Correct AnswerverifiedShow Answer

What is the wavelength of the photon emitted when a hydrogen atom makes a transition from the n = 4 state to the n = 1 state?

Correct AnswerverifiedShow Answer

An x-ray photon with wavelength 15.0 pm is scattered through 84.0° by an electron. What is the resulting kinetic energy of the electron?

Correct AnswerverifiedShow Answer

The energy of a photon of wavelength 400 nm is

Correct AnswerverifiedShow Answer

Correct Answer
verified

What is the radius of the ground state of He⁺?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

A laser beam emits 2.5 × 10²⁰ photons per second with a wavelength of 663 nm. What is the power output of this laser?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

What is the energy of a photon emitted in a transition from the n = 3 state to the n = 2 state in He⁺?

Correct Answer
verified

Correct Answer
verified

A photon of frequency 6.40 × 10¹⁴ Hz has what energy?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified