Halliday/Resnick/Walker Fundamentals of Physics 8th edition

1
Halliday/Resnick/WalkerFundamentals of Physics
8th edition

• Classroom Response System Questions

Chapter 22 Electric Fields
Reading Quiz Questions
2
22.2.1. 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 distance of the
particle from that location.
3
22.2.1. 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 distance of the
particle from that location.
4
22.2.2. Which of the following combination of
units are those for the strength of the electric
field? a) b) c) d) e)
5
22.2.2. Which of the following combination of
units are those for the strength of the electric
field? a) b) c) d) e)
6
22.2.3. Which one of the following statements
best describes the concept of the electric
field? a) The electric field is a vector
quantity that is the reaction force of
electrons. b) The electric field at each point
is the potential energy of a test charge divided
by the amount of the test charge. c) The
electric field is a distribution of vectors at
points due to the presence of one or more charged
objects. d) The electric field is a scalar
quantity related to the total amount of charge on
one or more charged objects. e) The electric
field is a scalar field, which has a magnitude at
each given point, similar to the temperature or
pressure field.
7
22.2.3. Which one of the following statements
best describes the concept of the electric
field? a) The electric field is a vector
quantity that is the reaction force of
electrons. b) The electric field at each point
is the potential energy of a test charge divided
by the amount of the test charge. c) The
electric field is a distribution of vectors at
points due to the presence of one or more charged
objects. d) The electric field is a scalar
quantity related to the total amount of charge on
one or more charged objects. e) The electric
field is a scalar field, which has a magnitude at
each given point, similar to the temperature or
pressure field.
8
22.3.1. 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.
9
22.3.1. 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.
10
22.3.2. Consider the following observations (1)
electric field lines are drawn connecting two
point charges labeled A and B, (2) charge A is
due north of charge B, and (3) a proton placed at
the mid-point on a line connecting the two point
charges travels due south. Which one of the
following statements correctly indicates the
signs of the two charges? a) Charge A is
positive and charge B is negative. b) Charge A
is positive and charge B is positive. c) Charge
A is negative and charge B is positive. d)
Charge A is negative and charge B is negative.
11
22.3.2. Consider the following observations (1)
electric field lines are drawn connecting two
point charges labeled A and B, (2) charge A is
due north of charge B, and (3) a proton placed at
the mid-point on a line connecting the two point
charges travels due south. Which one of the
following statements correctly indicates the
signs of the two charges? a) Charge A is
positive and charge B is negative. b) Charge A
is positive and charge B is positive. c) Charge
A is negative and charge B is positive. d)
Charge A is negative and charge B is negative.
12
22.3.3. The direction of the electric field is
the same as which of the following properties
related to a test charge? a) velocity of the
test charge b) force on a positive test
charge c) acceleration of a negative test
charge d) displacement of a moving test
charge e) None of the above choices are related
to the direction of the electric field.
13
22.3.3. The direction of the electric field is
the same as which of the following properties
related to a test charge? a) velocity of the
test charge b) force on a positive test
charge c) acceleration of a negative test
charge d) displacement of a moving test
charge e) None of the above choices are related
to the direction of the electric field.
14
22.3.4. Complete the following statement
Electric field lines depend on a) the direction
of the electric field. b) the strength of the
electric field. c) the force exerted on a test
charge. d) All of the above choices correctly
complete the statement. e) None of the choices
correctly complete the statement.
15
22.3.4. Complete the following statement
Electric field lines depend on a) the direction
of the electric field. b) the strength of the
electric field. c) the force exerted on a test
charge. d) All of the above choices correctly
complete the statement. e) None of the choices
correctly complete the statement.
16
22.4.1. Which one of the following statements
best describes the electric field at a distance r
from the electron? a) The electric field is
directed toward the electron and has a magnitude
of ke/r2. b) The electric field is directed
away from the electron and has a magnitude of
ke/r2. c) The electric field is directed toward
the electron and has a magnitude of ke/r. d)
The electric field is directed away from the
electron and has a magnitude of ke/r. e) The
electric field is directed toward the electron
and has a magnitude of ke2/r.
17
22.4.1. Which one of the following statements
best describes the electric field at a distance r
from the electron? a) The electric field is
directed toward the electron and has a magnitude
of ke/r2. b) The electric field is directed
away from the electron and has a magnitude of
ke/r2. c) The electric field is directed toward
the electron and has a magnitude of ke/r. d)
The electric field is directed away from the
electron and has a magnitude of ke/r. e) The
electric field is directed toward the electron
and has a magnitude of ke2/r.
18
22.4.2. Consider the field lines shown in the
drawing. Which one of the following statements
concerning this situation is true? a) These
field lines are those for a positively charged
particle. b) These field lines are those for a
negatively charged particle. c) These field
lines are those for a positively charged
particle and a negatively charged particle. d)
These field lines are those for two positively
charged particles. e) These field lines are
those for two negatively charged particles.
19
22.4.2. Consider the field lines shown in the
drawing. Which one of the following statements
concerning this situation is true? a) These
field lines are those for a positively charged
particle. b) These field lines are those for a
negatively charged particle. c) These field
lines are those for a positively charged
particle and a negatively charged particle. d)
These field lines are those for two positively
charged particles. e) These field lines are
those for two negatively charged particles.
20
22.4.3. Consider the field lines shown in the
drawing. Which one of the following statements
concerning this situation is true? a) A is a
positively charged particle and B is negatively
charged. b) B is a positively charged particle
and A is negatively charged. c) A and B are
both positively charged. d) A and B are both
negatively charged.
21
22.4.3. Consider the field lines shown in the
drawing. Which one of the following statements
concerning this situation is true? a) A is a
positively charged particle and B is negatively
charged. b) B is a positively charged particle
and A is negatively charged. c) A and B are
both positively charged. d) A and B are both
negatively charged.
22
22.5.1. Which one of the following expressions
gives the correct relationship between the
electric field strength E and the distance r from
an electric dipole? a) b) c) d) e)
23
22.5.1. Which one of the following expressions
gives the correct relationship between the
electric field strength E and the distance r from
an electric dipole? a) b) c) d) e)
24
22.5.2. Why does the electric field due to a
dipole decrease more rapidly with increasing
distance than that for a single charge? a) The
two charges in the dipole are separated by some
distance. b) Because there are two charges in
the dipole, the electric field has one-half the
field strength of a single charge. c) Any given
point is closer to one of the charges of the
dipole than to the other. d) The total charge
of the dipole is neutral (zero). e) Dipoles do
not produce a significant electric field.
25
22.5.2. Why does the electric field due to a
dipole decrease more rapidly with increasing
distance than that for a single charge? a) The
two charges in the dipole are separated by some
distance. b) Because there are two charges in
the dipole, the electric field has one-half the
field strength of a single charge. c) Any given
point is closer to one of the charges of the
dipole than to the other. d) The total charge
of the dipole is neutral (zero). e) Dipoles do
not produce a significant electric field.
26
22.5.3. 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.
27
22.5.3. 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.
28
22.6.1. Consider the following hypothetical
situation An infinitely long line of charge is
located along the central axis of an infinitely
long hollow cylinder of charge. 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.
29
22.6.1. Consider the following hypothetical
situation An infinitely long line of charge is
located along the central axis of an infinitely
long hollow cylinder of charge. 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.
30
22.6.2. 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.
31
22.6.2. 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.
32
22.6.3. Consider the drawing which shows a
uniform ring of charge of radius R. Which of the
following expressions gives the correct
dependence of the electric field at point P
located on the z axis, where z gtgt
R? a) b) c) d) e)
33
22.6.3. Consider the drawing which shows a
uniform ring of charge of radius R. Which of the
following expressions gives the correct
dependence of the electric field at point P
located on the z axis, where z gtgt
R? a) b) c) d) e)
34
22.7.1. Which of the following expressions gives
the electric field due to an infinite sheet of
charge with a uniform charge density
?? a) b) c) d) e)
35
22.7.1. Which of the following expressions gives
the electric field due to an infinite sheet of
charge with a uniform charge density
?? a) b) c) d) e)
36
22.8.1. Two positively charged particles are in
fixed locations on the x axis. A test charge
that is free to move about the x-y plane is
placed at the mid-point between the two
positively charged particles. If the test charge
is held stationary at the mid-point and then
released, it remains stationary. Which of the
following is the best explanation for this
behavior? a) The test charge is at a point of
stable equilibrium for both the x and y
directions. b) The test charge is at a point of
stable equilibrium for the x direction, but not
for the y direction. c) The test charge is at a
point of stable equilibrium for the y direction,
but not for the x direction. d) The test charge
is at a point of unstable equilibrium for both
the x direction and the y direction. e) No
forces are acting on the test charge.
37
22.8.1. Two positively charged particles are in
fixed locations on the x axis. A test charge
that is free to move about the x-y plane is
placed at the mid-point between the two
positively charged particles. If the test charge
is held stationary at the mid-point and then
released, it remains stationary. Which of the
following is the best explanation for this
behavior? a) The test charge is at a point of
stable equilibrium for both the x and y
directions. b) The test charge is at a point of
stable equilibrium for the x direction, but not
for the y direction. c) The test charge is at a
point of stable equilibrium for the y direction,
but not for the x direction. d) The test charge
is at a point of unstable equilibrium for both
the x direction and the y direction. e) No
forces are acting on the test charge.
38
22.9.1. A dipole is located within a uniform
electric field and aligned perpendicular to the
field. Why is the electrostatic potential energy
is equal to zero joules in this situation? a)
There is no force acting on the dipole. Only a
torque is acting on it. b) There is no torque
acting on the dipole when the dipole is parallel
or antiparallel to the field, so when the dipole
is perpendicular, the potential energy must be
zero joules. c) Because the zero potential
energy position is arbitrary, you may choose it
to be anything. d) If the dipole is parallel
or antiparallel to the electric field it must
have correspondingly opposite signs, therefore
when it is perpendicular to the field, the energy
must be zero joules. e) Dipoles have no
interaction with electric fields since their net
charge is zero coulombs, so the potential energy
is always zero joules.
39
22.9.1. A dipole is located within a uniform
electric field and aligned perpendicular to the
field. Why is the electrostatic potential energy
is equal to zero joules in this situation? a)
There is no force acting on the dipole. Only a
torque is acting on it. b) There is no torque
acting on the dipole when the dipole is parallel
or antiparallel to the field, so when the dipole
is perpendicular, the potential energy must be
zero joules. c) Because the zero potential
energy position is arbitrary, you may choose it
to be anything. d) If the dipole is parallel
or antiparallel to the electric field it must
have correspondingly opposite signs, therefore
when it is perpendicular to the field, the energy
must be zero joules. e) Dipoles have no
interaction with electric fields since their net
charge is zero coulombs, so the potential energy
is always zero joules.
40
22.9.2. Consider the dipole shown in a uniform
electric field. Which of the following occurs as
the dipole aligns itself with the electric
field? a) The electric field breaks the dipole
into two separate charges. b) The total energy
of the dipole and electric field decreases. c)
The potential energy of the electric field and
the dipole does not change. d) The potential
energy of the electric field and the dipole
increases. e) The potential energy of the
electric field and the dipole decreases.
41
22.9.2. Consider the dipole shown in a uniform
electric field. Which of the following occurs as
the dipole aligns itself with the electric
field? a) The electric field breaks the dipole
into two separate charges. b) The total energy
of the dipole and electric field decreases. c)
The potential energy of the electric field and
the dipole does not change. d) The potential
energy of the electric field and the dipole
increases. e) The potential energy of the
electric field and the dipole decreases.