PHYS212 Reading Quizzes & Exam prep
Which one of the following statements concerning the electric force is true?
A) Two charged objects with identical charges will exert an attractive force on one another.
B) It is possible for a small negatively-charged particle to float above a negatively charged surface.
C) A positively-charged object is attracted toward another positively-charged object.
D) The electric force cannot alter the motion of an object.
E) Newton's third law of motion does not apply to the electrostatic force. - correct answersIt is possible
for a small negatively-charged particle to float above a negatively charged surface.
Silicon is an example of what type of material? - correct answerssemiconductor
The unit of electrical current is the ampere (A). Which one of the combinations of units below is
equivalent to the ampere?
A) C·s
B) C/s
C) N·m/s
D) J·s
E) kg·m²/s - correct answersC/s
Which force is responsible for holding together the protons in the nucleus of an atom? (See the Sample
Problem called "Mutual electric repulsion in a nucleus.")
A) the electrostatic force
B) the gravitational force
C) the weak nuclear force
D) the strong nuclear force
E) No force is necessary. - correct answersthe strong nuclear force
Which one of the following statements concerning the electric field is false?
A) The SI unit of the electric field is the newton per meter (N/m).
B) The electric field is a vector quantity.
C) At a given point, a charged particle will experience a force if an electric field is present at that
location.
D) If a positively-charged particle is placed at a location where the electric field is directed due north, it
will be accelerated due north.
E) The magnitude of the electric field at a particular location due to a particular charged particle is
inversely proportional to the square of the distance of the particle from that location. - correct
answersThe SI unit of the electric field is the newton per meter (N/m).
Which of the following statements concerning electric field lines is false?
A) Electric field lines between two charged particles are often curved.
B) Electric field lines are a method proposed by Michael Faraday to map the electric field at various
locations.
C) Electric field lines can be used to indicate the local magnitude of the electric field.
D) Electric field lines are always directed radially away from a positively-charged particle.
E) An electric field line indicates the direction of the force on an electron placed on the line. - correct
answersAn electric field line indicates the direction of the force on an electron placed on the line.
,Why does the electric field due to a dipole decrease more rapidly with increasing distance than that for
a single charge? - correct answersThe total charge of the dipole is neutral (zero).
Which one of the following statements concerning the electric dipole moment is false?
A) The dipole moment is a scalar quantity.
B) The dipole moment has units of C·m.
C) The dipole moment combines two intrinsic properties of an electric dipole, the distance between the
charges and the amount of charge on each object.
D) The dipole moment is directed from the negative charge toward the positive charge of the dipole.
E) The direction of the dipole moment is used to specify the orientation of the dipole. - correct
answersThe dipole moment is a scalar quantity.
Consider the following hypothetical situation: An infinitely long line of charge (uniform density) is
located along the central axis of an infinitely long hollow cylinder of charge (uniform density). Which of
the following statements concerning the force on the line of charge is true?
A) The force on the line of charge is infinite.
B) The force on the line of charge is zero newtons.
C) The force depends on the radius of the cylinder. It will be larger if the cylinder radius is large.
D) The force depends on the radius of the cylinder. It will be smaller if the cylinder radius is large. -
correct answersThe force on the line of charge is zero newtons.
Which one of the following statements concerning charge distributions is false?
A) Charge distributions consist of a very large number of closely spaced charges.
B) Charge distributions may be uniform arrangements of charges along a line, over a surface, or
throughout a volume.
C) Calculus provides important tools for determining electric fields due to charge distributions.
D) Charge distributions are treated as being composed of discrete charges.
E) In dealing with charge distributions, it is often more useful to speak in terms of a charge density
rather than the total charge. - correct answersCharge distributions are treated as being composed of
discrete charges.
An electron traveling horizontally to the right enters a region where a uniform electric field is directed
downward. What is the direction of the force exerted on the electron once it has entered the field? -
correct answersupward
A dipole is located within a uniform electric field and aligned perpendicular to the field. Why is the
electrostatic potential energy equal to zero joules in this situation? - correct answersBecause the zero
potential energy configuration is arbitrary, you may choose it to be anything, and this is the standard
convention.
In July, Joe set up his fixed array of solar panels to maximize the amount of electricity output from the
array when the Sun was high in the sky. Unfortunately, Joe finds that the array doesn't operate as well
during the winter months. What is the most likely cause of Joe's winter problem? - correct answersThe
sun is lower in the sky during the winter, so sunlight strikes the solar panels at an angle.
, A spherical Gaussian surface of radius R is surrounding a particle with a net charge q. If the spherical
Gaussian surface is replaced by a cube, under what conditions would the total electric flux through the
sides of the cube be the same as through the spherical surface?
A) under all conditions
B) if the sides of the cube are of length R
C) if the sides of the cube are of length 2R
D) if the diagonals of the cube are of length 2R
E) under no conditions - correct answersunder all conditions
Which of the following laws or principles can be derived from Gauss' law?
A) Amonton's law
B) Coulomb's law
C) Carnot's principle
D) definition of a fluxon
E) electric flux principle - correct answersCoulomb's law
Which of the following statements concerning the electric field inside a conductor is true?
A) The electric field inside a conductor is never zero.
B) The electric field inside a conductor is always zero.
C) The electric field inside a conductor is always zero if charges inside the conductor are not moving.
D) The electric field inside a conductor is always zero unless there are excess charges inside the
conductor. - correct answersThe electric field inside a conductor is always zero if charges inside the
conductor are not moving.
Why must the electric field at the surface of a conductor be perpendicular to the surface? - correct
answersIf it was not perpendicular, then charges on the surface would be moving.
What is the best choice for the shape of a Gaussian surface?
A) spherical
B) cylindrical
C) cubic
D) It should be one that encloses the smallest volume.
E) It should be one that matches the symmetry of the charge distribution. - correct answersIt should be
one that matches the symmetry of the charge distribution.
Which of the following units are the SI units for the electric potential?
A) ampere (A)
B) newton/coulomb (N/C)
C) joule (J)
D) gauss (G)
E) volt (V) - correct answersvolt (V)
Points A, B, and C lie along a line from left to right, respectively. Point B is at a lower electric potential
than point A. Point C is at a lower electric potential than point B. Which one of the following statements
best describes the subsequent motion, if any, of a positively-charged particle released from rest at point
B?
A) The particle will move at constant velocity in the direction of point A.
B) The particle will move at constant velocity in the direction of point C.
Which one of the following statements concerning the electric force is true?
A) Two charged objects with identical charges will exert an attractive force on one another.
B) It is possible for a small negatively-charged particle to float above a negatively charged surface.
C) A positively-charged object is attracted toward another positively-charged object.
D) The electric force cannot alter the motion of an object.
E) Newton's third law of motion does not apply to the electrostatic force. - correct answersIt is possible
for a small negatively-charged particle to float above a negatively charged surface.
Silicon is an example of what type of material? - correct answerssemiconductor
The unit of electrical current is the ampere (A). Which one of the combinations of units below is
equivalent to the ampere?
A) C·s
B) C/s
C) N·m/s
D) J·s
E) kg·m²/s - correct answersC/s
Which force is responsible for holding together the protons in the nucleus of an atom? (See the Sample
Problem called "Mutual electric repulsion in a nucleus.")
A) the electrostatic force
B) the gravitational force
C) the weak nuclear force
D) the strong nuclear force
E) No force is necessary. - correct answersthe strong nuclear force
Which one of the following statements concerning the electric field is false?
A) The SI unit of the electric field is the newton per meter (N/m).
B) The electric field is a vector quantity.
C) At a given point, a charged particle will experience a force if an electric field is present at that
location.
D) If a positively-charged particle is placed at a location where the electric field is directed due north, it
will be accelerated due north.
E) The magnitude of the electric field at a particular location due to a particular charged particle is
inversely proportional to the square of the distance of the particle from that location. - correct
answersThe SI unit of the electric field is the newton per meter (N/m).
Which of the following statements concerning electric field lines is false?
A) Electric field lines between two charged particles are often curved.
B) Electric field lines are a method proposed by Michael Faraday to map the electric field at various
locations.
C) Electric field lines can be used to indicate the local magnitude of the electric field.
D) Electric field lines are always directed radially away from a positively-charged particle.
E) An electric field line indicates the direction of the force on an electron placed on the line. - correct
answersAn electric field line indicates the direction of the force on an electron placed on the line.
,Why does the electric field due to a dipole decrease more rapidly with increasing distance than that for
a single charge? - correct answersThe total charge of the dipole is neutral (zero).
Which one of the following statements concerning the electric dipole moment is false?
A) The dipole moment is a scalar quantity.
B) The dipole moment has units of C·m.
C) The dipole moment combines two intrinsic properties of an electric dipole, the distance between the
charges and the amount of charge on each object.
D) The dipole moment is directed from the negative charge toward the positive charge of the dipole.
E) The direction of the dipole moment is used to specify the orientation of the dipole. - correct
answersThe dipole moment is a scalar quantity.
Consider the following hypothetical situation: An infinitely long line of charge (uniform density) is
located along the central axis of an infinitely long hollow cylinder of charge (uniform density). Which of
the following statements concerning the force on the line of charge is true?
A) The force on the line of charge is infinite.
B) The force on the line of charge is zero newtons.
C) The force depends on the radius of the cylinder. It will be larger if the cylinder radius is large.
D) The force depends on the radius of the cylinder. It will be smaller if the cylinder radius is large. -
correct answersThe force on the line of charge is zero newtons.
Which one of the following statements concerning charge distributions is false?
A) Charge distributions consist of a very large number of closely spaced charges.
B) Charge distributions may be uniform arrangements of charges along a line, over a surface, or
throughout a volume.
C) Calculus provides important tools for determining electric fields due to charge distributions.
D) Charge distributions are treated as being composed of discrete charges.
E) In dealing with charge distributions, it is often more useful to speak in terms of a charge density
rather than the total charge. - correct answersCharge distributions are treated as being composed of
discrete charges.
An electron traveling horizontally to the right enters a region where a uniform electric field is directed
downward. What is the direction of the force exerted on the electron once it has entered the field? -
correct answersupward
A dipole is located within a uniform electric field and aligned perpendicular to the field. Why is the
electrostatic potential energy equal to zero joules in this situation? - correct answersBecause the zero
potential energy configuration is arbitrary, you may choose it to be anything, and this is the standard
convention.
In July, Joe set up his fixed array of solar panels to maximize the amount of electricity output from the
array when the Sun was high in the sky. Unfortunately, Joe finds that the array doesn't operate as well
during the winter months. What is the most likely cause of Joe's winter problem? - correct answersThe
sun is lower in the sky during the winter, so sunlight strikes the solar panels at an angle.
, A spherical Gaussian surface of radius R is surrounding a particle with a net charge q. If the spherical
Gaussian surface is replaced by a cube, under what conditions would the total electric flux through the
sides of the cube be the same as through the spherical surface?
A) under all conditions
B) if the sides of the cube are of length R
C) if the sides of the cube are of length 2R
D) if the diagonals of the cube are of length 2R
E) under no conditions - correct answersunder all conditions
Which of the following laws or principles can be derived from Gauss' law?
A) Amonton's law
B) Coulomb's law
C) Carnot's principle
D) definition of a fluxon
E) electric flux principle - correct answersCoulomb's law
Which of the following statements concerning the electric field inside a conductor is true?
A) The electric field inside a conductor is never zero.
B) The electric field inside a conductor is always zero.
C) The electric field inside a conductor is always zero if charges inside the conductor are not moving.
D) The electric field inside a conductor is always zero unless there are excess charges inside the
conductor. - correct answersThe electric field inside a conductor is always zero if charges inside the
conductor are not moving.
Why must the electric field at the surface of a conductor be perpendicular to the surface? - correct
answersIf it was not perpendicular, then charges on the surface would be moving.
What is the best choice for the shape of a Gaussian surface?
A) spherical
B) cylindrical
C) cubic
D) It should be one that encloses the smallest volume.
E) It should be one that matches the symmetry of the charge distribution. - correct answersIt should be
one that matches the symmetry of the charge distribution.
Which of the following units are the SI units for the electric potential?
A) ampere (A)
B) newton/coulomb (N/C)
C) joule (J)
D) gauss (G)
E) volt (V) - correct answersvolt (V)
Points A, B, and C lie along a line from left to right, respectively. Point B is at a lower electric potential
than point A. Point C is at a lower electric potential than point B. Which one of the following statements
best describes the subsequent motion, if any, of a positively-charged particle released from rest at point
B?
A) The particle will move at constant velocity in the direction of point A.
B) The particle will move at constant velocity in the direction of point C.
