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Cutnell/Johnson
Physics 7th edition
Classroom Response System Questions
Chapter 32 Maxwell’s Equations: Magnetism of
Matter
Reading Quiz Questions
32.2.1. Complete the following statement: According to today’s
scientists, magnetic monopoles
a) have no mass.
b) have no charge.
c) are found in abundance in the most distant parts of the universe.
d) do not exist anywhere in the universe.
e) are the antiparticles for magnetic dipoles.
32.2.1. Complete the following statement: According to today’s
scientists, magnetic monopoles
a) have no mass.
b) have no charge.
c) are found in abundance in the most distant parts of the universe.
d) do not exist anywhere in the universe.
e) are the antiparticles for magnetic dipoles.
32.2.2. What would you get if you took a bar magnet and cut it in half?
a) two pieces, one a north pole and one a south pole
b) two shorter magnets, each with a north pole and a south pole
c) two pieces, both non-magnetic
d) a molten mess from the energy released from within the magnet
upon cutting
e) an electric shock
32.2.2. What would you get if you took a bar magnet and cut it in half?
a) two pieces, one a north pole and one a south pole
b) two shorter magnets, each with a north pole and a south pole
c) two pieces, both non-magnetic
d) a molten mess from the energy released from within the magnet
upon cutting
e) an electric shock
32.2.3. Which of the following choices concerning the net magnetic flux
through any enclosed surface is true according to Gauss’ law for
magnetic fields?
a) The net magnetic flux in this case would be a vector quantity equal to the
enclosed magnetic field.
b) The net magnetic flux in this case would be a vector quantity equal to the
number of magnetic monopoles passing through the surface per unit
time.
c) The net magnetic flux in this case would be a positive scalar quantity.
d) The net magnetic flux in this case would be equal to zero.
e) The net magnetic flux in this case would be a negative scalar quantity.
32.2.3. Which of the following choices concerning the net magnetic flux
through any enclosed surface is true according to Gauss’ law for
magnetic fields?
a) The net magnetic flux in this case would be a vector quantity equal to the
enclosed magnetic field.
b) The net magnetic flux in this case would be a vector quantity equal to the
number of magnetic monopoles passing through the surface per unit
time.
c) The net magnetic flux in this case would be a positive scalar quantity.
d) The net magnetic flux in this case would be equal to zero.
e) The net magnetic flux in this case would be a negative scalar quantity.
32.3.1. What is produced from a changing electric field?
a) an electric field directed perpendicularly to the changing field
b) a magnetic flux
c) a magnetic field directed perpendicularly to the changing field
d) lightning
e) an electric field directed parallel to the changing field
32.3.1. What is produced from a changing electric field?
a) an electric field directed perpendicularly to the changing field
b) a magnetic flux
c) a magnetic field directed perpendicularly to the changing field
d) lightning
e) an electric field directed parallel to the changing field
32.3.2. A parallel plate capacitor is being charged by a constant current i. During the
charging, the electric field within the plates is increasing with time. Which one
of the following statements concerning the magnetic field between the plates is
true?
a) The magnetic field within a parallel plate capacitor is always equal to zero tesla.
b) The induced magnetic field is directed antiparallel to the increasing electric field.
c) The induced magnetic field strength has its largest value at the center of the plates
and decreases linearly toward the edges of the plates.
d) The induced magnetic field strength has the same magnitude within the plates of
the capacitor, except near the edges, at a given time.
e) The induced magnetic field strength is zero tesla near the center of the plates and
increases as r increases toward the edges of the plates.
32.3.2. A parallel plate capacitor is being charged by a constant current i. During the
charging, the electric field within the plates is increasing with time. Which one
of the following statements concerning the magnetic field between the plates is
true?
a) The magnetic field within a parallel plate capacitor is always equal to zero tesla.
b) The induced magnetic field is directed antiparallel to the increasing electric field.
c) The induced magnetic field strength has its largest value at the center of the plates
and decreases linearly toward the edges of the plates.
d) The induced magnetic field strength has the same magnitude within the plates of
the capacitor, except near the edges, at a given time.
e) The induced magnetic field strength is zero tesla near the center of the plates and
increases as r increases toward the edges of the plates.
32.4.1. What is a displacement current?
a) a fictitious current across the plates of a capacitor
b) charged particles moving in a changing magnetic field
c) charged particle moving in a changing electric field
d) the movement of the positive nuclei within atoms in response to a
changing electric field
e) the movement of the positive nuclei within atoms in response to a
changing magnetic field
32.4.1. What is a displacement current?
a) a fictitious current across the plates of a capacitor
b) charged particles moving in a changing magnetic field
c) charged particle moving in a changing electric field
d) the movement of the positive nuclei within atoms in response to a
changing electric field
e) the movement of the positive nuclei within atoms in response to a
changing magnetic field
32.4.2. By making use of the concept of displacement current, we can find the
induced magnetic field strength within a charging capacitor. Consider a parallel
plate capacitor with circular plates of radius R. Which of the following
expressions gives the correct relationship between the induced magnetic field
strength B at radius r from the center?
Br
1
b) B 
r
a)
c) B = constant
d) B  r 2
e) B 
1
r2
32.4.2. By making use of the concept of displacement current, we can find the
induced magnetic field strength within a charging capacitor. Consider a parallel
plate capacitor with circular plates of radius R. Which of the following
expressions gives the correct relationship between the induced magnetic field
strength B at radius r from the center?
Br
1
b) B 
r
a)
c) B = constant
d) B  r 2
e) B 
1
r2
32.5.1. Which one of the following is not one of Maxwell’s
fundamental equations of electromagnetism?
a) Gauss’ law for electricity
b) Coulomb’s law
c) Faraday’s law
d) Ampere-Maxwell law
e) Gauss’ law for magnetism
32.5.1. Which one of the following is not one of Maxwell’s
fundamental equations of electromagnetism?
a) Gauss’ law for electricity
b) Coulomb’s law
c) Faraday’s law
d) Ampere-Maxwell law
e) Gauss’ law for magnetism
32.6.1. Which one of the following choices is the generally accepted
reason for the changing of the Earth’s magnetic field over time?
a) The field has changed because the Hubble constant has changed.
b) The field has changed as the Earth has gone through numerous
global warming and cooling cycles.
c) The field has changed as the Earth’s rotation has slowed down over
time.
d) The field has changed as a result of numerous asteroid collisions
with the Earth over time.
e) The reason for the changing field has yet to be determined.
32.6.1. Which one of the following choices is the generally accepted
reason for the changing of the Earth’s magnetic field over time?
a) The field has changed because the Hubble constant has changed.
b) The field has changed as the Earth has gone through numerous
global warming and cooling cycles.
c) The field has changed as the Earth’s rotation has slowed down over
time.
d) The field has changed as a result of numerous asteroid collisions
with the Earth over time.
e) The reason for the changing field has yet to be determined.
32.6.2. The direction of the magnetic field at any location of the
Earth’s surface is commonly specified in terms of two field angles.
What are the names given to these two angles?
a) latitude and longitude
b) oblique and obtuse
c) dihedral and euclidean
d) squine and novile
e) declination and inclination
32.6.2. The direction of the magnetic field at any location of the
Earth’s surface is commonly specified in terms of two field angles.
What are the names given to these two angles?
a) latitude and longitude
b) oblique and obtuse
c) dihedral and euclidean
d) squine and novile
e) declination and inclination
32.6.3. What are the stones called that were initially discovered by the
ancient Greek and Chinese peoples that are naturally occurring
magnetic materials?
a) pyrite
b) lodestones
c) compass stones
d) sorcerer stone
e) hematite
32.6.3. What are the stones called that were initially discovered by the
ancient Greek and Chinese peoples that are naturally occurring
magnetic materials?
a) pyrite
b) lodestones
c) compass stones
d) sorcerer stone
e) hematite
32.7.1. Which of the following is most responsible for the magnetic
behavior of materials?
a) neutrons
b) protons
c) photons
d) electrons
e) phonons
32.7.1. Which of the following is most responsible for the magnetic
behavior of materials?
a) neutrons
b) protons
c) photons
d) electrons
e) phonons
32.7.2. Which one of the following statements concerning the measured values
of the spin angular momentum is true?
a) The measured component of the spin angular momentum can only have one
of two possible values that differ only in the sign.
b) The spin angular momentum can be oriented only in the direction an electron
is moving.
c) The spin angular momentum can be easily measured in today’s laboratories.
d) The spin angular momentum is the same thing as angular momentum, except
that it is the angular momentum of an electron.
e) The spin angular momentum does not contribute to the magnetic properties
of materials.
32.7.2. Which one of the following statements concerning the measured values
of the spin angular momentum is true?
a) The measured component of the spin angular momentum can only have one
of two possible values that differ only in the sign.
b) The spin angular momentum can be oriented only in the direction an electron
is moving.
c) The spin angular momentum can be easily measured in today’s laboratories.
d) The spin angular momentum is the same thing as angular momentum, except
that it is the angular momentum of an electron.
e) The spin angular momentum does not contribute to the magnetic properties
of materials.
32.8.1. Which one of the following statements is true for paramagnetic
materials?
a) The atoms have no permanent magnetic dipole moments under any
condition.
b) The atoms have permanent magnetic dipole moments that are mostly aligned
with each other.
c) The atoms have permanent magnetic dipole moments that are randomly
oriented.
d) The atoms have permanent magnetic dipole moments that are aligned either
parallel or antiparallel with each other.
e) The atoms have dipole moments that align in opposition to an applied
magnetic field, but otherwise have no permanent dipole moments.
32.8.1. Which one of the following statements is true for paramagnetic
materials?
a) The atoms have no permanent magnetic dipole moments under any
condition.
b) The atoms have permanent magnetic dipole moments that are mostly aligned
with each other.
c) The atoms have permanent magnetic dipole moments that are randomly
oriented.
d) The atoms have permanent magnetic dipole moments that are aligned either
parallel or antiparallel with each other.
e) The atoms have dipole moments that align in opposition to an applied
magnetic field, but otherwise have no permanent dipole moments.
32.8.2. Which of the following terms is used to describe materials that
have regions in which strong magnetic dipole moments are aligned
with each other?
a) diamagnetic
b) paramagnetic
c) ferromagnetic
d) ferrimagnetic
e) gaussetic
32.8.2. Which of the following terms is used to describe materials that
have regions in which strong magnetic dipole moments are aligned
with each other?
a) diamagnetic
b) paramagnetic
c) ferromagnetic
d) ferrimagnetic
e) gaussetic
32.8.3. What produces the magnetism of an individual atom?
a) the nuclear force that holds protons within the atomic nucleus
b) the orbital and spin motions of electrons
c) the motion of the atom itself
d) the electric interaction between electrons and protons
e) neutrons are naturally magnetic
32.8.3. What produces the magnetism of an individual atom?
a) the nuclear force that holds protons within the atomic nucleus
b) the orbital and spin motions of electrons
c) the motion of the atom itself
d) the electric interaction between electrons and protons
e) neutrons are naturally magnetic
32.9.1. Which of the following terms is used to describe materials that
have weak induced magnetic dipole moments that are directed in
the opposite direction to an applied external magnetic field?
a) diamagnetic
b) paramagnetic
c) ferromagnetic
d) ferrimagnetic
e) gaussetic
32.9.1. Which of the following terms is used to describe materials that
have weak induced magnetic dipole moments that are directed in
the opposite direction to an applied external magnetic field?
a) diamagnetic
b) paramagnetic
c) ferromagnetic
d) ferrimagnetic
e) gaussetic
32.11.1. What is the name given to the quantum mechanical effect that
gives rise to ferromagnetism in materials, such as iron, cobalt, and
nickel?
a) parity
b) nuclear magnetic resonance
c) cooper pairing
d) quantization
e) exchange coupling
32.11.1. What is the name given to the quantum mechanical effect that
gives rise to ferromagnetism in materials, such as iron, cobalt, and
nickel?
a) parity
b) nuclear magnetic resonance
c) cooper pairing
d) quantization
e) exchange coupling
32.11.2. Which one of the following materials is not ferromagnetic?
a) cobalt
b) nickel
c) gadolinium
d) iron
e) aluminum
32.11.2. Which one of the following materials is not ferromagnetic?
a) cobalt
b) nickel
c) gadolinium
d) iron
e) aluminum