Question 1

What is the shortest x-ray wavelength that can be produced in a 12-keV x-ray machine?

Accepted Answer

The answer of What is the shortest x-ray wavelength that...

Question 2

A photon collides with an electron.After the collision the wavelength of the scattered wave at a scattering angle greater than is:

Accepted Answer

A) greater than or equal to the initial wavelength. 
B) equal to the initial wavelength. 
C) less than or equal to the initial wavelength. 
D) greater than the initial wavelength. 
E) less or greater depending on the scattering angle. 
A) greater than or equal to the initial wavelength. 
B) equal to the initial wavelength. 
C) less than or equal to the initial wavelength. 
D) greater than the initial wavelength. 
E) less or greater depending on the scattering angle. D

Question 3

The wavelength of a 45-kg teenager moving at 5 m/s on a skateboard is about:

Accepted Answer

A) 5 * 10-37 m. 
B) 3 * 10-36 m. 
C) 7 * 10-34 m. 
D) 0.1 m. 
E) 5 m. 
A) 5 * 10-37 m. 
B) 3 * 10-36 m. 
C) 7 * 10-34 m. 
D) 0.1 m. 
E) 5 m. B

Question 4

The threshold wavelength for photoelectric emission of a particular substance is 500 nm.What is the work function (in eV)?

Accepted Answer

A) 4.2 
B) 4.0 *10-19 
C) 4.0 * 10-10 
D) 2.5 * 10-19 
E) 2.5 
A) 4.2 
B) 4.0 *10-19 
C) 4.0 * 10-10 
D) 2.5 * 10-19 
E) 2.5

Question 5

Light is emitted by hydrogen atoms in the visible range for a hydrogen atom.Its wavelength is 656 nm.What value of n is associated with the light? (RH = 1.097 * 107 m-1)

Accepted Answer

A) 5 
B) 2 
C) 4 
D) 3 
E) 6 
A) 5 
B) 2 
C) 4 
D) 3 
E) 6

Question 6

An electron is accelerated through a potential difference of 25 000 V.What is the de Broglie wavelength of the electron (in m)?

Accepted Answer

A) 5.9 *10-12 
B) 6.8 * 10-12 
C) 6.5 *10-12 
D) 7.8 * 10-12 
E) 5.5 *10-12 
A) 5.9 *10-12 
B) 6.8 * 10-12 
C) 6.5 *10-12 
D) 7.8 * 10-12 
E) 5.5 *10-12

Question 7

What is the maximum kinetic energy (in eV) of a photoelectron emitted from a surface whose work function is 5.0 eV when illuminated by a light whose wavelength is 200 nm?

Accepted Answer

A) 1.9 
B) 1.2 
C) 3.1 
D) zero 
E) 6.2 
A) 1.9 
B) 1.2 
C) 3.1 
D) zero 
E) 6.2

Question 8

What is the maximum kinetic energy (in eV) of a photoelectron when a surface, whose work function is 5.0 eV, is illuminated by photons whose wavelength is 400 nm?

Accepted Answer

A) 3.1 
B) (-1.9) 
C) 1.9 
D) 0 
E) 1.2 
A) 3.1 
B) (-1.9) 
C) 1.9 
D) 0 
E) 1.2

Question 9

Your temperature is 98.6 $\degree$F.Assuming your skin is a perfect radiator ($\varepsilon$= 1), determine the wavelength corresponding to the largest intensity (in $\mu$m).

Accepted Answer

A) 8.0 
B) 9.3 
C) 3.0 
D) 5.7 
E) 29.4 
A) 8.0 
B) 9.3 
C) 3.0 
D) 5.7 
E) 29.4

Question 10

Film behind a double slit is exposed to light in the following way: First one slit is opened and light is allowed to go through that slit for time $\Delta$t.Then it is closed and the other slit is opened and light is allowed to go through that slit for the same time $\Delta$t.When the film is developed the pattern will be:

Accepted Answer

A) one single slit pattern. 
B) two superimposed single slit patterns, their centres displaced from each other by the distance between the two slits. 
C) one double slit pattern. 
D) two double slit patterns, their centres displaced from each other by the distance between the two slits. 
E) random darkening of the film.(no pattern at all) 
A) one single slit pattern. 
B) two superimposed single slit patterns, their centres displaced from each other by the distance between the two slits. 
C) one double slit pattern. 
D) two double slit patterns, their centres displaced from each other by the distance between the two slits. 
E) random darkening of the film.(no pattern at all)

Question 11

What wavelength (in$\mu$m) is associated with the Paschen series for n = 4? (RH = 1.097 * 107 m-1)

Accepted Answer

A) 320 
B) 530 
C) 2.7 
D) 1.9 
E) 0.5 
A) 320 
B) 530 
C) 2.7 
D) 1.9 
E) 0.5

Question 12

A solid state pulsed laser has an energy of 400 mJ per pulse.If its wavelength is 1.06 * 10-6 m, how many photons are in each pulse?

Accepted Answer

A) 2 * 1025 
B) 2 * 1021 
C) 3 *1018 
D) 6 * 1038 
E) 2 * 1018 
A) 2 * 1025 
B) 2 * 1021 
C) 3 *1018 
D) 6 * 1038 
E) 2 * 1018

Question 13

Photoelectrons are ejected when monochromatic light shines on a freshly-prepared (oxide-free) sodium surface.In order to obtain the maximum increase in the number of electrons ejected per second, the experimenter needs to:

Accepted Answer

A) increase the frequency of the light. 
B) increase the intensity of the light. 
C) increase the area illuminated by the light. 
D) increase the frequency and intensity of the light, and also the area illuminated. 
E) increase the intensity of the light and the area illuminated, but not the frequency. 
A) increase the frequency of the light. 
B) increase the intensity of the light. 
C) increase the area illuminated by the light. 
D) increase the frequency and intensity of the light, and also the area illuminated. 
E) increase the intensity of the light and the area illuminated, but not the frequency.

Question 14

What is the energy in eV of a photon of yellow light? $\lambda$ = 500 nm.

Accepted Answer

The answer of What is the energy in eV of...

Question 15

A neutron has a mass of 1.67 *10-27 kg.The de Broglie wavelength is 1.4 * 10-10 m.How fast is the neutron going? (in m/s)

Accepted Answer

A) 3.4 * 103 
B) 2.8 * 103 
C) 3.9 *103 
D) 2.6 *103 
E) 1.7 * 103 
A) 3.4 * 103 
B) 2.8 * 103 
C) 3.9 *103 
D) 2.6 *103 
E) 1.7 * 103

Question 16

When a photon collides with a free electron at rest and the direction of motion of the photon changes:

Accepted Answer

A) the magnitude of the momentum of the photon does not change. 
B) the momentum of the electron does not change. 
C) the kinetic energy of the electron does not change. 
D) the total energy of the photon does not change. 
E) both the magnitude of the momentum and the total energy of the photon decrease. 
A) the magnitude of the momentum of the photon does not change. 
B) the momentum of the electron does not change. 
C) the kinetic energy of the electron does not change. 
D) the total energy of the photon does not change. 
E) both the magnitude of the momentum and the total energy of the photon decrease.

Question 17

An atomic level has a lifetime,  of.What is the linewidth, , of this level?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 18

The experimental observation(s) below that require(s) a quantum explanation for the photoelectric effect:

Accepted Answer

A) is that more photoelectrons are emitted when the light frequency increases. 
B) is that the maximum kinetic energy of the photoelectrons is related linearly to the frequency of the light. 
C) is that every metal surface has a work function, a minimum amount of energy needed to free electrons. 
D) is that the stopping potential measures the kinetic energy of the photoelectrons. 
E) are all of the above. 
A) is that more photoelectrons are emitted when the light frequency increases. 
B) is that the maximum kinetic energy of the photoelectrons is related linearly to the frequency of the light. 
C) is that every metal surface has a work function, a minimum amount of energy needed to free electrons. 
D) is that the stopping potential measures the kinetic energy of the photoelectrons. 
E) are all of the above.

Question 19

If a rubidium surface is irradiated with blue light of wavelength 450.0 nm, what is the kinetic energy of the electrons emitted? (The work function for rubidium is $\phi$ = 2.09 eV.)

Accepted Answer

The answer of If a rubidium surface is irradiated with...

Question 20

A wave packet can represent a quantum particle because:

Accepted Answer

A) it has the localised nature of a particle. 
B) the group velocity is identical to the speed of the particle. 
C) the waves that compose the packet can show interference and diffraction. 
D) of all of the above. 
E) of only (a) and (b) above. 
A) it has the localised nature of a particle. 
B) the group velocity is identical to the speed of the particle. 
C) the waves that compose the packet can show interference and diffraction. 
D) of all of the above. 
E) of only (a) and (b) above.

Exam 17: Quantisation and Wave-Particle Duality

What is the shortest x-ray wavelength that can be produced in a 12-keV x-ray machine?

A photon collides with an electron.After the collision the wavelength of the scattered wave at a scattering angle greater than is:

The wavelength of a 45-kg teenager moving at 5 m/s on a skateboard is about:

The threshold wavelength for photoelectric emission of a particular substance is 500 nm.What is the work function (in eV)?

Light is emitted by hydrogen atoms in the visible range for a hydrogen atom.Its wavelength is 656 nm.What value of n is associated with the light? (RH = 1.097 * 107 m-1)

An electron is accelerated through a potential difference of 25 000 V.What is the de Broglie wavelength of the electron (in m)?

What is the maximum kinetic energy (in eV) of a photoelectron emitted from a surface whose work function is 5.0 eV when illuminated by a light whose wavelength is 200 nm?

What is the maximum kinetic energy (in eV) of a photoelectron when a surface, whose work function is 5.0 eV, is illuminated by photons whose wavelength is 400 nm?

Your temperature is 98.6 °\degree° F.Assuming your skin is a perfect radiator ( ε\varepsilonε = 1), determine the wavelength corresponding to the largest intensity (in μ\muμ m).

What wavelength (in μ\muμ m) is associated with the Paschen series for n = 4? (RH = 1.097 * 107 m-1)

A solid state pulsed laser has an energy of 400 mJ per pulse.If its wavelength is 1.06 * 10-6 m, how many photons are in each pulse?

Photoelectrons are ejected when monochromatic light shines on a freshly-prepared (oxide-free) sodium surface.In order to obtain the maximum increase in the number of electrons ejected per second, the experimenter needs to:

What is the energy in eV of a photon of yellow light? λ\lambdaλ = 500 nm.

A neutron has a mass of 1.67 *10-27 kg.The de Broglie wavelength is 1.4 * 10-10 m.How fast is the neutron going? (in m/s)

When a photon collides with a free electron at rest and the direction of motion of the photon changes:

An atomic level has a lifetime, of.What is the linewidth, , of this level?

The experimental observation(s) below that require(s) a quantum explanation for the photoelectric effect:

If a rubidium surface is irradiated with blue light of wavelength 450.0 nm, what is the kinetic energy of the electrons emitted? (The work function for rubidium is ϕ\phiϕ = 2.09 eV.)

A wave packet can represent a quantum particle because:

Electric Fields

Gausss Law

Electric Potential

Energy and Capacitance

Current and Resistance

Direct-Current Circuits

Magnetic Fields

Magnetic Forces

Faradays Law

Inductance

Alternating-Current Circuits

Electromagnetic Waves

The Nature of Light and the Principles of Ray Optics

Image Formation

Wave Optics

Diffraction Patterns and Polarisation

Introduction to Quantum Mechanics

Atomic Physics

Quantum Physics of Molecules and Solids

Nuclei and Radioactivity

Particle Physics

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Your temperature is 98.6 $\degree$ F.Assuming your skin is a perfect radiator ( $\varepsilon$ = 1), determine the wavelength corresponding to the largest intensity (in $\mu$ m).

What wavelength (in $\mu$ m) is associated with the Paschen series for n = 4? (RH = 1.097 * 107 m-1)

What is the energy in eV of a photon of yellow light? $\lambda$ = 500 nm.

A neutron has a mass of 1.67 10-27 kg.The de Broglie wavelength is 1.4 10-10 m.How fast is the neutron going? (in m/s)

If a rubidium surface is irradiated with blue light of wavelength 450.0 nm, what is the kinetic energy of the electrons emitted? (The work function for rubidium is $\phi$ = 2.09 eV.)