Question 1

The figure shows two different orientations of a proton in a magnetic field. Which orientation is at higher energy?

Accepted Answer

A)  a 
B)  b 
C)  Both are at the same energy, and there is no other orientation at higher energy. 
D)  Both are at the same energy, but if the spin vector were perpendicular to the magnetic field the energy would be higher. 
E)  Both are at the same energy, but if the spin vector were perpendicular to the magnetic field the energy would be lower. 
A)  a 
B)  b 
C)  Both are at the same energy, and there is no other orientation at higher energy. 
D)  Both are at the same energy, but if the spin vector were perpendicular to the magnetic field the energy would be higher. 
E)  Both are at the same energy, but if the spin vector were perpendicular to the magnetic field the energy would be lower. B

Question 2

In a helium-neon laser, the laser light arises from a transition from a _________ state to a _________ state:

Accepted Answer

A)  He, He 
B)  Ne, Ne 
C)  He, Ne 
D)  Ne, He 
E)  N, He 
A)  He, He 
B)  Ne, Ne 
C)  He, Ne 
D)  Ne, He 
E)  N, He B

Question 3

For any atom other that hydrogen and helium all electrons in the same shell have:

Accepted Answer

A)  the same energy 
B)  the same magnitude of angular momentum 
C)  the same magnetic quantum number 
D)  the same spin quantum number 
E)  none of the above 
A)  the same energy 
B)  the same magnitude of angular momentum 
C)  the same magnetic quantum number 
D)  the same spin quantum number 
E)  none of the above E

Question 4

A magnetic dipole is placed between the poles of a magnet as shown. The direction of the associated force exerted on the dipole is:

Accepted Answer

A)  positive x 
B)  positive y 
C)  negative x 
D)  negative y 
E)  into or out of the page 
A)  positive x 
B)  positive y 
C)  negative x 
D)  negative y 
E)  into or out of the page

Question 5

If electrons did not have intrinsic angular momentum (spin) but still obeyed the Pauli exclusion principle the states occupied by electrons in the ground state of helium would be:

Accepted Answer

A)  (n = 1, ℓ=0); (n = 1, ℓ=0) 
B)  (n = 1, ℓ=0); (n = 1, ℓ=1) 
C)  (n = 1, ℓ=0); (n = 2, ℓ=0) 
D)  (n = 2, ℓ=0); (n = 2, ℓ=1) 
E)  (n = 2, ℓ=1); (n = 2, ℓ=1) 
A)  (n = 1, ℓ=0); (n = 1, ℓ=0) 
B)  (n = 1, ℓ=0); (n = 1, ℓ=1) 
C)  (n = 1, ℓ=0); (n = 2, ℓ=0) 
D)  (n = 2, ℓ=0); (n = 2, ℓ=1) 
E)  (n = 2, ℓ=1); (n = 2, ℓ=1)

Question 6

The purpose of the mirrors at the ends of a helium-neon laser is:

Accepted Answer

A)  to assure that no laser light leaks out 
B)  to increase the number of stimulated emissions 
C)  to absorb some of the photons 
D)  to keep the light used for pumping inside the laser 
E)  to double the effective length of the laser 
A)  to assure that no laser light leaks out 
B)  to increase the number of stimulated emissions 
C)  to absorb some of the photons 
D)  to keep the light used for pumping inside the laser 
E)  to double the effective length of the laser

Question 7

Two different electron beams are incident on two different targets and both produce x rays. The cutoff wavelength for target 1 is shorter than the cutoff wavelength for target 2. We can conclude that:

Accepted Answer

A)  target 2 has a higher atomic number than target 1 
B)  target 2 has a lower atomic number than target 1 
C)  the electrons in beam 1 have greater kinetic energy than those in beam 2 
D)  the electrons in beam 1 have less kinetic energy than those in beam 2 
E)  target 1 is thicker than target 2 
A)  target 2 has a higher atomic number than target 1 
B)  target 2 has a lower atomic number than target 1 
C)  the electrons in beam 1 have greater kinetic energy than those in beam 2 
D)  the electrons in beam 1 have less kinetic energy than those in beam 2 
E)  target 1 is thicker than target 2

Question 8

A metastable state is important for the generation of a laser beam because it assures that:

Accepted Answer

A)  spontaneous emission does not occur more often than stimulated emission 
B)  photons do not split too rapidly 
C)  more photons are emitted than are absorbed 
D)  photons do not collide with each other 
E)  photons do not make upward transitions 
A)  spontaneous emission does not occur more often than stimulated emission 
B)  photons do not split too rapidly 
C)  more photons are emitted than are absorbed 
D)  photons do not collide with each other 
E)  photons do not make upward transitions

Question 9

An electron in an atom is in a state with principal quantum number n = 4. The possible values of the orbital quantum number ℓ are:

Accepted Answer

A)  1, 2, 3 
B)  1, 2, 3, 4 
C)  -3, -2, -1, 0, 1, 2, 3 
D)  0, 1, 2, 3 
E)  0, 1, 2 
A)  1, 2, 3 
B)  1, 2, 3, 4 
C)  -3, -2, -1, 0, 1, 2, 3 
D)  0, 1, 2, 3 
E)  0, 1, 2

Question 10

Space quantization means that:

Accepted Answer

A)  space is quantized 
B)  Lz can have only certain discrete values 
C)  and are in the same direction 
D)  and are in opposite directions 
E)  an electron has a magnetic dipole moment 
A)  space is quantized 
B)  Lz can have only certain discrete values 
C)  and are in the same direction 
D)  and are in opposite directions 
E)  an electron has a magnetic dipole moment

Question 11

When a lithium atom is made from a helium atom by adding a proton (and neutron) to the nucleus and an electron outside, the electron goes into an n = 2, ℓ=0 state rather than an n = 1, ℓ=0 state. This is an indication that electrons:

Accepted Answer

A)  obey the Pauli exclusion principle 
B)  obey the minimum energy principle 
C)  undergo the Zeeman effect 
D)  are diffracted 
E)  and protons are interchangeable 
A)  obey the Pauli exclusion principle 
B)  obey the minimum energy principle 
C)  undergo the Zeeman effect 
D)  are diffracted 
E)  and protons are interchangeable

Question 12

The magnetic field is along the z axis in a Stern-Gerlach experiment. The force it exerts on a magnetic dipole with dipole moment is proportional to:

Accepted Answer

A)    
B)  B2 
C)  dB/dz 
D)  d2B/dz2 
E)  $\int$B dz 
A)    
B)  B2 
C)  dB/dz 
D)  d2B/dz2 
E)  $\int$B dz

Question 13

Five electrons are in a two-dimensional square potential energy well with sides of length L. The potential energy is infinite at the sides and zero inside. The single-particle energies are given by where nx and ny are integers. The energy of the ground state of the system is

Accepted Answer

A)  0 
B)  10 (h2/8mL2) 
C)  19 (h2/8mL2) 
D)  24 (h2/8mL2) 
E)  48 (h2/8mL2) 
A)  0 
B)  10 (h2/8mL2) 
C)  19 (h2/8mL2) 
D)  24 (h2/8mL2) 
E)  48 (h2/8mL2)

Question 14

A group of electromagnetic waves might   Which of these describe the waves from a laser?

Accepted Answer

A)  I only 
B)  II only 
C)  III only 
D)  I and II only 
E)  I, II, and III 
A)  I only 
B)  II only 
C)  III only 
D)  I and II only 
E)  I, II, and III

Question 15

The quantity sz is related to the quantum number ms by:

Accepted Answer

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

Question 16

Five electrons are in a two-dimensional square potential energy well with sides of length L. The potential energy is infinite at the sides and zero inside. The single-particle energies are given by where nx and ny are integers. The energy of the first excited state of the system is:

Accepted Answer

A)  13 (h2/8mL2) 
B)  22 (h2/8mL2) 
C)  24 (h2/8mL2) 
D)  25 (h2/8mL2) 
E)  27 (h2/8mL2) 
A)  13 (h2/8mL2) 
B)  22 (h2/8mL2) 
C)  24 (h2/8mL2) 
D)  25 (h2/8mL2) 
E)  27 (h2/8mL2)

Question 17

The number of states in a shell with principal quantum number n = 3 is:

Accepted Answer

A)  3 
B)  8 
C)  9 
D)  18 
E)  32 
A)  3 
B)  8 
C)  9 
D)  18 
E)  32

Question 18

The "e" in laser stands for:

Accepted Answer

A)  electric 
B)  emf 
C)  energy 
D)  emission 
E)  entropy 
A)  electric 
B)  emf 
C)  energy 
D)  emission 
E)  entropy

Question 19

The electron states in an atom which constitute a single shell all have:

Accepted Answer

A)  the same value of n 
B)  the same value of ℓ 
C)  the same value of n and the same value of ℓ 
D)  the same value of ℓ and the same value of mℓ 
E)  the same set of all four quantum numbers 
A)  the same value of n 
B)  the same value of ℓ 
C)  the same value of n and the same value of ℓ 
D)  the same value of ℓ and the same value of mℓ 
E)  the same set of all four quantum numbers

Question 20

The number of possible values of the magnetic quantum number mℓ associated with a given value of the orbital quantum number ℓ is:

Accepted Answer

A)  1 
B)  2 
C)  ℓ 
D)  2 ℓ 
E)  2 ℓ +1 
A)  1 
B)  2 
C)  ℓ 
D)  2 ℓ 
E)  2 ℓ +1

Exam 40: All About Atoms

The figure shows two different orientations of a proton in a magnetic field. Which orientation is at higher energy?

In a helium-neon laser, the laser light arises from a transition from a _________ state to a _________ state:

For any atom other that hydrogen and helium all electrons in the same shell have:

A magnetic dipole is placed between the poles of a magnet as shown. The direction of the associated force exerted on the dipole is:

If electrons did not have intrinsic angular momentum (spin) but still obeyed the Pauli exclusion principle the states occupied by electrons in the ground state of helium would be:

The purpose of the mirrors at the ends of a helium-neon laser is:

Two different electron beams are incident on two different targets and both produce x rays. The cutoff wavelength for target 1 is shorter than the cutoff wavelength for target 2. We can conclude that:

A metastable state is important for the generation of a laser beam because it assures that:

An electron in an atom is in a state with principal quantum number n = 4. The possible values of the orbital quantum number ℓ are:

Space quantization means that:

When a lithium atom is made from a helium atom by adding a proton (and neutron) to the nucleus and an electron outside, the electron goes into an n = 2, ℓ=0 state rather than an n = 1, ℓ=0 state. This is an indication that electrons:

The magnetic field is along the z axis in a Stern-Gerlach experiment. The force it exerts on a magnetic dipole with dipole moment is proportional to:

Five electrons are in a two-dimensional square potential energy well with sides of length L. The potential energy is infinite at the sides and zero inside. The single-particle energies are given by where nx and ny are integers. The energy of the ground state of the system is

A group of electromagnetic waves might Which of these describe the waves from a laser?

The quantity sz is related to the quantum number ms by:

Five electrons are in a two-dimensional square potential energy well with sides of length L. The potential energy is infinite at the sides and zero inside. The single-particle energies are given by where nx and ny are integers. The energy of the first excited state of the system is:

The number of states in a shell with principal quantum number n = 3 is:

The "e" in laser stands for:

The electron states in an atom which constitute a single shell all have:

The number of possible values of the magnetic quantum number mℓ associated with a given value of the orbital quantum number ℓ is:

Measurement

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Motion in Two and Three Dimensions

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Kinetic Energy and Work

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Center of Mass and Linear Momentum

Rotation

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Equilibrium and Elasticity

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Filters

In a helium-neon laser, the laser light arises from a transition from a _ state to a _ state:

Five electrons are in a two-dimensional square potential energy well with sides of length L. The potential energy is infinite at the sides and zero inside. The single-particle energies are given by where n_x and n_y are integers. The energy of the ground state of the system is

The quantity s_z is related to the quantum number m_sby:

Five electrons are in a two-dimensional square potential energy well with sides of length L. The potential energy is infinite at the sides and zero inside. The single-particle energies are given by where n_x and n_y are integers. The energy of the first excited state of the system is:

The number of possible values of the magnetic quantum number m_ℓ associated with a given value of the orbital quantum number ℓ is: