Question 1

A particle is moving in a circular orbit about a fixed center of a two-dimensional harmonic oscillator. The ground-state (n = 1) energy is 1.0 eV. What is the energy of the second excited level (n = 3)?

Accepted Answer

A) 0.33 eV 
B) 3.0 eV 
C) 0.1 eV 
D) 9.0 eV 
E) 1.0 eV

Question 2

A discrete spectrum is one that

Accepted Answer

A) only has wavelengths longer than the visible. 
B) never yields a line spectrum. 
C) yields a line spectrum. 
D) has continuous wavelengths. 
E) only has wavelengths in the visible.

Question 3

As a result of Compton scattering, the scattered photon has

Accepted Answer

A) a longer wavelength than the incident photon. 
B) a wavelength 24 pm shorter than the incident photon. 
C) the same wavelength as the incident photon. 
D) a wavelength 32 pm shorter than the incident photon. 
E) a shorter wavelength than the incident photon.

Question 4

A gamma ray has an energy of 1 MeV.
(a) What is the frequency associated with this photon?
(b) What is the wavelength associated with this photon?

Accepted Answer

The answer of A gamma ray has an energy of...

Question 5

In hydrogen any transition ending in the ground state emits a photon that

Accepted Answer

A) may be in the ultraviolet. 
B) is in neither the ultraviolet nor the infrared. 
C) may be in the infrared. 
D) is in the infrared. 
E) is in the ultraviolet.

Question 6

Light with a wavelength of 310 nm is incident on a metal that has a work function of 3.8 eV. What is the maximum kinetic energy that a photoelectron ejected in this process can have?

Accepted Answer

A) 0.62 × 10-19 J 
B) 0.21 × 10-19 J 
C) 0.36 × 10-19 J 
D) 0.48 × 10-19 J 
E) 0.33 × 10-19 J

Question 7

Electrons come in discrete units of well defined mass and charge, but they also have wave properties.

Accepted Answer

A) True 
 B)False

Question 8

A blackbody is a perfect emitter of the radiation it generates.

Accepted Answer

A) True 
 B)False

Question 9

What is the energy of a 633 nm photon?

Accepted Answer

A) 0.32 eV 
B) 3.14 eV 
C) 5.1 eV 
D) 1.96 eV 
E) 0.51 eV

Question 10

The part of an electron microscope that plays the same role as the lenses do in an optical microscope is

Accepted Answer

A) the vacuum chamber. 
B) the coils. 
C) the cathode. 
D) the anode. 
E) the deflector plates.

Question 11

A light-emitting diode emits one microwatt of 640 nm photons. How many photons are emitted each second?

Accepted Answer

A) 2.5 × 1020 
B) 9.7 × 1020 
C) 2.0 × 1031 
D) 3.0 × 1021 
E) 3.2 × 1012

Question 12

The radius of the n = 3 Bohr orbit in the hydrogen atom is

Accepted Answer

A) 0.36 nm. 
B) 0.60 nm. 
C) 0.48 nm. 
D) 0.12 nm. 
E) 0.24 nm.

Question 13

The energy of an ultraviolet photon is more than the energy of an infrared photon.

Accepted Answer

A) True 
 B)False

Question 14

In the spectrum of white light which one of the following colors corresponds to the lowest temperature?

Accepted Answer

A) Yellow 
B) Blue 
C) Red 
D) Green 
E) Orange

Question 15

If the momentum of an electron is 1.95 × 10-27 kg∙m/s, what is its de Broglie wavelength?

Accepted Answer

A) 340 nm 
B) 210 nm 
C) 170 nm 
D) 420 nm 
E) 520 nm

Question 16

What is the magnitude of the energy difference between the lowest energy of a hydrogen atom (n = 1) and the second excited state (n = 3)?

Accepted Answer

A) 27.4 eV 
B) 9.07 eV 
C) 1.51 eV 
D) 109 eV 
E) 12.1 eV

Question 17

A proton and an electron are both accelerated to the same final speed. If λp is the de Broglie wavelength of the proton and λe is the de Broglie wavelength of the electron, then

Accepted Answer

A) λp > λe. 
B) λp = λe. 
C) λp e. 
D) Not enough data to answer this question.

Question 18

What wavelength corresponds to the n = 2 → n = 1 transition in singly-ionized helium?

Accepted Answer

A) 15.2 nm 
B) 22.8 nm 
C) 4.56 nm 
D) 11.4 nm 
E) 30.4 nm

Question 19

Planck's constant

Accepted Answer

A) sets an upper limit to the amount of energy that can be absorbed or emitted. 
B) sets a lower limit to the amount of energy that can be absorbed or emitted. 
C) relates mass to energy. 
D) relates mass to velocity. 
E) none of the given answers

Question 20

When a proton passes through matter, it is possible for it to interact with the matter in such a way that an electron and a positron are produced; this interaction is referred to as

Accepted Answer

A) the photoelectric effect. 
B) the Compton effect. 
C) the de Broglie effect. 
D) pair production. 
E) none of the given answers

Exam 37: Early Quantum Theory and Models of the Atom

A particle is moving in a circular orbit about a fixed center of a two-dimensional harmonic oscillator. The ground-state (n = 1) energy is 1.0 eV. What is the energy of the second excited level (n = 3) ?

A discrete spectrum is one that

As a result of Compton scattering, the scattered photon has

A gamma ray has an energy of 1 MeV. (a) What is the frequency associated with this photon? (b) What is the wavelength associated with this photon?

In hydrogen any transition ending in the ground state emits a photon that

Light with a wavelength of 310 nm is incident on a metal that has a work function of 3.8 eV. What is the maximum kinetic energy that a photoelectron ejected in this process can have?

Electrons come in discrete units of well defined mass and charge, but they also have wave properties.

A blackbody is a perfect emitter of the radiation it generates.

What is the energy of a 633 nm photon?

The part of an electron microscope that plays the same role as the lenses do in an optical microscope is

A light-emitting diode emits one microwatt of 640 nm photons. How many photons are emitted each second?

The radius of the n = 3 Bohr orbit in the hydrogen atom is

The energy of an ultraviolet photon is more than the energy of an infrared photon.

In the spectrum of white light which one of the following colors corresponds to the lowest temperature?

If the momentum of an electron is 1.95 × 10^-27 kg∙m/s, what is its de Broglie wavelength?

What is the magnitude of the energy difference between the lowest energy of a hydrogen atom (n = 1) and the second excited state (n = 3) ?

A proton and an electron are both accelerated to the same final speed. If λ_p is the de Broglie wavelength of the proton and λ_e is the de Broglie wavelength of the electron, then

What wavelength corresponds to the n = 2 → n = 1 transition in singly-ionized helium?

Planck's constant

When a proton passes through matter, it is possible for it to interact with the matter in such a way that an electron and a positron are produced; this interaction is referred to as