Physics Test #1

-The electric potential stays the same, but the electric potential energy doubles.

A +0.2 μC charge is in an electric field. What happens if that charge is replaced by a +0.4 μC charge? -The electric potential stays the same, but the electric potential energy doubles. -The electric potential doubles, but the electric potential energy stays the same. -Both the electric potential and electric potential energy double. -Both the electric potential and electric potential energy stay the same.

decreases, increases

A battery establishes a voltage V on a parallel-plate capacitor. After the battery is disconnected, the distance between the plates is doubled without loss of charge. Accordingly, the capacitance ________ and the voltage between the plates _________

The power dissipated is reduced by a factor of 2.

A constant voltage is applied across a circuit. If the resistance in the circuit is doubled, what is the effect on the power dissipated by the circuit? -The power dissipated is reduced by a factor of 2. -The power dissipated is quadrupled. -The power dissipated is doubled. -The power dissipated remains constant. -The power dissipated is reduced by a factor of 4.

The electric field decreases because of the insertion of the Teflon®.

A dielectric material, such as Teflon®, is placed between the plates of a parallel-plate capacitor without altering the structure of the capacitor. The charge on the capacitor is held fixed. How is the electric field between the plates of the capacitor affected? -The electric field is not altered, because the structure remains unchanged. -The electric field decreases because of the insertion of the Teflon®. -The electric field increases because of the insertion of the Teflon®. -The electric field becomes infinite because of the insertion of the Teflon®. -The electric field becomes zero after the insertion of the Teflon®.

E(πR2)sinϕ E(πR2)cosΘ

A disk with a radius of R is oriented with its normal unit vector at an angle Θ with respect to a uniform electric field. Which of the following represent the electric flux through the disk? Check all that apply. E(2πR)sinΘ E(πR2)cosϕ E(2πR)cosΘ E(πR2)sinϕ E(πR2)sinΘ E(πR2)cosΘ

-increasing the strength of the electric field -decreasing the given orientation angle of the disk -increasing the area of the disk

A disk with a radius of R is oriented with its normal unit vector at an angle θ with respect to a uniform electric field. Which of the following would result in an increase in the electric flux through the disk? Check all that apply. -increasing the strength of the electric field -decreasing the area of the disk -decreasing the strength of the electric field -increasing the given orientation angle of the disk, but not exceeding an angle of 90° -decreasing the given orientation angle of the disk -increasing the area of the disk

-The electric potential energy of the charge decreases, and the kinetic energy increases.

A negative charge moves in a direction opposite to that of an electric field. What happens to the energy associated with the charge? -The electric potential energy of the charge decreases, and the kinetic energy increases. -Both the electric potential energy and the kinetic energy of the charge increase. -The electric potential energy of the charge increases, and the kinetic energy decreases. -Both the electric potential energy and the kinetic energy of the charge decrease.

-The potential energy associated with the charge increases. -The electric field does negative work on the charge.

A negative charge moves in the direction of an electric field. Which of the following statements are true? Check all that apply. -The electric field does positive work on the charge. -The potential energy associated with the charge decreases. -The amount of work done on the charge cannot be determined without additional information. -The electric field does not do any work on the charge. -The potential energy associated with the charge increases. -The electric field does negative work on the charge.

-The field points away from the positive charge, and the force on the negative charge is in the opposite direction to the field.

A negative point charge is in an electric field created by a positive point charge. Part A Which of the following is true? -The field points away from the positive charge, and the force on the negative charge is in the opposite direction to the field. -The field points away from the positive charge, and the force on the negative charge is in the same direction as the field. -The field points toward the positive charge, and the force on the negative charge is in the same direction as the field. -The field points toward the positive charge, and the force on the negative charge is in the opposite direction to the field.

-The net charge uniformly distributes itself on the sphere's outer surface.

A net charge is placed on a hollow conducting sphere. How does the net charge distribute itself? -The net charge uniformly distributes itself on the sphere's inner and outer surfaces. -The net charge uniformly distributes itself throughout the thickness of the conducting sphere. -The net charge uniformly distributes itself on the sphere's inner surface. -The net charge uniformly distributes itself on the sphere's outer surface. -The net charge clumps together at some location within the sphere.

The energy stored in the capacitor doubles its original value.

A parallel-plate capacitor connected to a battery becomes fully charged. After the capacitor from the battery is disconnected, the separation between the plates of the capacitor is doubled in such a way that no charge leaks off. How is the energy stored in the capacitor affected? -The energy stored in the capacitor is decreased to one-half of its original value. -The energy stored in the capacitor doubles its original value. -The energy stored in the capacitor quadruples its original value. -The energy stored in the capacitor remains constant. -The energy stored in the capacitor is decreased to one-fourth of its original value.

-The fur acquires a positive charge.

A plastic rod is rubbed with a fur. During the rubbing process, the rod acquires a negative charge. What type of charge does the fur acquire? -The fur acquires a positive charge. -The fur acquires either a negative or positive charge, depending on how hard the rod was rubbed. -The fur remains neutral. -The fur also acquires a negative charge.

No work is performed or required in moving the positive charge from point A to point B.

A positive charge is moved from point A to point B along an equipotential surface. How much work is performed or required in moving the charge? -Work is performed in moving the positive charge from point A to point B. -Work is required in moving the positive charge from point A to point B. -Work is both performed and required in moving the charge from point A to point B. -No work is performed or required in moving the positive charge from point A to point B.

-The electric potential energy of the charge increases, and the kinetic energy decreases.

A positive charge moves in a direction opposite to that of an electric field. What happens to the energy associated with the charge? -The electric potential energy of the charge decreases, and the kinetic energy increases. -Both the electric potential energy and the kinetic energy of the charge increase. -The electric potential energy of the charge increases, and the kinetic energy decreases. -Both the electric potential energy and the kinetic energy of the charge decrease.

-The potential energy associated with the charge decreases. -The electric field does positive work on the charge

A positive charge moves in the direction of an electric field. Which of the following statements are true? Check all that apply. -The algebraic sign of the work done on the charge cannot be determined without additional information. -The potential energy associated with the charge increases. -The electric field does not do any work on the charge. -The potential energy associated with the charge decreases. -The electric field does negative work on the charge. -The electric field does positive work on the charge.

-The end of the metal rod closest to the positively charged rod acquires a negative charge.

A positively charged rod is brought close to one end of an uncharged metal rod but does not actually touch it. What type of charge does the end of the metal rod closest to the positively charged rod acquire? -The end of the metal rod closest to the positively charged rod can acquire either a positive or negative charge, depending on the composition of the metal. -The end of the metal rod closest to the positively charged rod remains neutral. -The end of the metal rod closest to the positively charged rod acquires a negative charge. -The end of the metal rod closest to the positively charged rod acquires a positive charge.

Both acquire the same kinetic energy.

A proton (Q = +e) and an electron (Q = -e) are in a constant electric field created by oppositely charged plates. You release the proton from near the positive plate and the electron from near the negative plate. When the proton and electron strike the opposite plate, which one has more kinetic energy? The electron. The proton. Both acquire the same kinetic energy. Neither−there is no change in kinetic energy. They both acquire the same kinetic energy but with opposite signs

The magnitude of the force is the same for both but in opposite directions.

A proton Q = +e and an electron Q = -e are in a constant electric field created by oppositely charged plates. You release the proton from near the positive plate and the electron from near the negative plate. Which feels the larger electric force? The proton. The electron. Neither−there is no force. The magnitude of the force is the same for both and in the same direction. The magnitude of the force is the same for both but in opposite directions.

negative or neutral.

A small metal ball hangs from the ceiling by an insulating thread. The ball is attracted to a positively charged rod held near the ball. Part A The charge of the ball must be negative or neutral. positive or neutral. positive. neutral. negative.

There is no electric field on the interior of the conducting sphere.

A solid conducting sphere is placed in an external uniform electric field. With regard to the electric field on the sphere's interior, which statement is correct? -There is no electric field on the interior of the conducting sphere. -The interior field points in a direction perpendicular to the exterior field. -The interior field points in a direction parallel to the exterior field. -The interior field points in a direction opposite to the exterior field.

decreases

As an object acquires a positive charge, its mass usually decreases. becomes negative. increases. stays the same.

Wire A and wire B have the same resistivity. Wire A has twice the resistance of wire B.

Consider two copper wires with the same cross-sectional area. Wire A is twice as long as wire B. How do the resistivities and resistances of the two wires compare? Check all that apply. Wire A and wire B have the same resistivity. Wire B has twice the resistivity of wire A. Wire A has twice the resistance of wire B. Wire A and wire B have the same resistance. Wire A has twice the resistivity of wire B. Wire B has twice the resistance of wire A.

S1 S3

Five point charges q and four Gaussian surfaces S are represented in the figure shown. Through which of the Gaussian surfaces are the total electric flux zero? Check all that apply. S1 S3 S2 S4 The total electric flux is not zero through any of the Gaussian surfaces.

2q/εo

Five point charges q and four Gaussian surfaces S are shown in the figure. What is the total electric flux through surface S2? q/εo zero 3q/εo 5q/εo 4q/εo 2q/εo

2q/εo

Five point charges q and four Gaussian surfaces S are shown. What is the total electric flux through surface S4? 3q/εo zero 2q/εo q/εo 4q/εo 5q/εo

E = 0, V ≠ 0.

Four identical point charges are arranged at the corners of a square [Hint: Draw a figure]. The electric field E and potential V at the center of the square are E ≠ 0, V ≠ 0. E = 0, V = 0. E = 0, V ≠ 0. E ≠ 0, V = 0. E = V regardless of the value.

They are attracted to each other by the same amount.

Fred the lightning bug has a mass m and a charge +q. Jane, his lightning-bug wife, has a mass of 34m and a charge −2q. Because they have charges of opposite sign, they are attracted to each other. Part A Which is attracted more to the other, and by how much? Jane, twice as much. Fred, twice as much. They are attracted to each other by the same amount. Jane, four times as much. Fred, four times as much.

-The total electric flux through the two surfaces is equal.

Gaussian surfaces A and B enclose the same positive point charge. The area of surface A is two times larger than that of surface B. How does the total electric flux through the two surfaces compare? -The total electric flux through surface B is eight times larger than that through surface A. -The total electric flux through surface A is four times larger than that through surface B. -The total electric flux through surface A is eight times larger than that through surface B. -The total electric flux through the two surfaces is equal. -The total electric flux through surface B is four times larger than that through surface A.

3W

If it takes an amount of work W to move two +q point charges from infinity to a distance d apart from each other, then how much work should it take to move three +q point charges from infinity to a distance d apart from each other? 2W. 3W. 4W. 6W.

The voltage is reduced by a factor of 2.

If the resistance in a circuit connected to a constant current is halved, how is the voltage in the circuit affected? -The voltage is reduced by a factor of 4. -The voltage is reduced by a factor of 2. -The voltage remains constant. -The voltage is doubled. -The voltage is quadrupled.

remain almost exactly the same.

If the two charged plates were moved until they are half the distance shown without changing the charge on the plates, the electric field near the center of the plates would remain almost exactly the same. increase by a factor of 2. decrease by a factor of 2. increase, but not by a factor of 2. decrease, but not by a factor of 2.

The current is doubled.

If the voltage across a circuit of constant resistance is doubled, how is the current in the circuit affected? -The current is reduced by a factor of 4. -The current is reduced by a factor of 2. -The current remains constant. -The current is quadrupled. -The current is doubled.

The current is doubled.

If the voltage across a circuit of constant resistance is doubled, how is the current in the circuit affected? The current is quadrupled. The current is doubled. The current is reduced by a factor of 2. The current remains constant. The current is reduced by a factor of 4.

The electric flux is the zero through the surface shown in (c).

In the figure, a uniform electric field is shown passing through a flat area A. In (a), the surface of area A is perpendicular to the electric field. In (b), the surface is tilted by an angle θ with respect to the electric field. In (c), the surface is parallel to the electric field. In which orientation is the electric flux through the surface the equal to zero? -The electric flux is zero through all of the surfaces shown. -The electric flux is the zero through the surface shown in (b). -The electric flux is the zero through the surface shown in (c). -The electric flux is nonzero and equal through all of the surfaces shown. -The electric flux is the zero through the surface shown in (a).

-The electric flux is the largest through the surface shown in (a).

In the figure, a uniform electric field is shown passing through a flat area A. In (a), the surface of area A is perpendicular to the electric field. In (b), the surface is tilted by an angle θ with respect to the electric field. In (c), the surface is parallel to the electric field. In which orientation is the electric flux through the surface the largest? -The electric flux is the largest through the surface shown in (b). -The electric flux is nonzero and equal through all of the surfaces shown. -The electric flux is zero through all of the surfaces shown. -The electric flux is the largest through the surface shown in (c). -The electric flux is the largest through the surface shown in (a).

-Yes, regardless of the magnitude of the two charges.

Is it possible for the electric field between two positive charges to equal zero along the line joining the two charges? -Yes, but only if the two charges are equal in magnitude. -Yes, regardless of the magnitude of the two charges. -No, a zero electric field cannot exist between the two charges. -This cannot be determined without knowing the separation between the two charges.

There is little to no voltage drop between a bird's two feet, but there is a significant voltage drop between the top of a ladder touching a power line and the bottom of the ladder on the ground.

Nothing happens when birds land on a power line, yet we are warned not to touch a power line with a ladder. What is the difference? -Most birds don't understand the situation. -There is little to no voltage drop between a bird's two feet, but there is a significant voltage drop between the top of a ladder touching a power line and the bottom of the ladder on the ground. -Dangerous current comes from the ground only. -Birds have extremely high internal resistance compared to humans.

-It is attractive and directed in the +x direction.

Q1 = -0.10 μC is located at the origin. Q2 = +0.10 μC is located on the positive x axis at x = 1.0 m. Part A Which of the following is true of the force on Q1 due to Q2? -It is attractive and directed in the −x direction. -It is repulsive and directed in the +x direction. -It is repulsive and directed in the −x direction. -It is attractive and directed in the +x direction.

-It is attractive and directed in the −x direction.

Q2 = +0.10μC is located at the origin. Q1 = -0.10μC is located on the positive x axis at x = 1.0 m. Part A Which of the following is true of the force on Q1 due to Q2? -It is attractive and directed in the +x direction. -It is attractive and directed in the −x direction. -It is repulsive and directed in the −x direction. -It is repulsive and directed in the +x direction.

At twice the distance, the electric potential is V/2.

The electric potential at a certain distance from a point charge can be represented by V. What is the value of the electric potential at twice the distance from the point charge? -At twice the distance, the electric potential is V/4. -At twice the distance, the electric potential remains V. -At twice the distance, the electric potential is 4V. -At twice the distance, the electric potential is 2V. -At twice the distance, the electric potential is V/2.

-If you triple the value of the charge, the electric potential is 3V.

The electric potential at a certain location from a point charge can be represented by V. What is the value of the electric potential at the same location if the strength of the charge is tripled? -If you triple the value of the charge, the electric potential is 3V. -If you triple the value of the charge, the electric potential is 9V. -If you triple the value of the charge, the electric potential is V/9. -If you triple the value of the charge, the electric potential remains V. -If you triple the value of the charge, the electric potential is V/3.

If you triple the value of the charge, the electric potential is 3V

The electric potential at a certain location from a point charge can be represented by V. What is the value of the electric potential at the same location if the strength of the charge is tripled? -If you triple the value of the charge, the electric potential is V/3. -If you triple the value of the charge, the electric potential is 3V. -If you triple the value of the charge, the electric potential remains V. -If you triple the value of the charge, the electric potential is V/9. -If you triple the value of the charge, the electric potential is 9V.

Va

The figure shows the electric potential V at five locations in a uniform electric field. At which point is the electric potential the largest? Vb Vc Vd Ve Va

Va

The figure shows the electric potential V at five locations in a uniform electric field. At which point is the electric potential the largest? Vd Vc Ve Va Vb

Vb Vd

The figure shows the electric potential V at five locations in a uniform electric field. At which points is the electric potential equal? Check all that apply. Vc Va Vb Vd Ve

The strength of the electric field decreases during this process.

The plates of a parallel-plate capacitor are maintained with a constant voltage by a battery as they are pulled apart. How is the strength of the electric field affected during this process? -The strength of the electric field remains constant. -The strength of the electric field increases during this process. -The electric field between the plates becomes infinite. -The strength of the electric field decreases during this process. -The electric field between the plates becomes zero.

The amount of charge on the plates increases during this process.

The plates of a parallel-plate capacitor are maintained with a constant voltage by a battery as they are pushed together, without touching. How is the amount of charge on the plates affected during this process? -The amount of charge on the plates decreases during this process. -The amount of charge remains constant. -The amount of charge on the plates becomes zero. -The amount of charge on the plates increases during this process.

-At twice the distance, the strength of the field is E/4.

The strength of the electric field at a certain distance from a point charge is represented by E. What is the strength of the electric field at twice the distance from the point charge? -At twice the distance, the strength of the field is 2E. -At twice the distance, the strength of the field is E/2. -At twice the distance, the strength of the field remains equal to E. -At twice the distance, the strength of the field is 4E. -At twice the distance, the strength of the field is E/4.

inside a metal car.

To be safe during a lightning storm, it is best to be inside a wooden building without any grounding. on a metal observation tower. inside a metal car. in the middle of a grassy meadow. next to a tall tree in a forest.

-The charged objects exert electrostatic forces on each other that are equal in magnitude and opposite in direction.

Two charged objects are separated by some distance. The charge on the first object is greater than the charge on the second object. How does the force between the two objects compare? -The charged objects exert electrostatic forces on each other that are equal in magnitude and opposite in direction. -The second object exerts a large electrostatic force on the first object. -The charged objects exert electrostatic forces on each other that are equal in magnitude and pointing in the same direction. -The first object exerts a large electrostatic force on the second object.

-The force between them quadruples.

Two charged objects separated by some distance attract each other. If the charges on both objects are doubled with no change in distance between them, what happens to the magnitude of the force between the objects? -The force between them is halved. -The force between them is quartered. -The force between them also doubles. -The force between them quadruples. -The force between them remains unchanged.

-the electric field is zero and the potential is positive.

Two identical positive charges are placed near each other. At the point halfway between the two charges, -the electric field is not zero and the potential is positive. -the electric field is zero and the potential is positive. -the electric field is not zero and the potential is zero. -the electric field is zero and the potential is zero. -None of these statements is true.

-most everyday objects have as many plus charges as minus charges.

We are usually not aware of the electric force acting between two everyday objects because -the electric force is one of the weakest forces in nature. -most everyday objects have as many plus charges as minus charges. -the electric force is due to microscopic-sized particles such as electrons and protons. -the electric force is invisible.

less than

We wish to determine the electric field at a point near a positively charged metal sphere (a good conductor). We do so by bringing a small positive test charge, q0, to this point and measure the force F0 on it. The magnitude of F0 /q0 will be ____________ the magnitude of the electric field E as it was at that point before the test charge was present. less than greater than equal to

-The field at point 1 is larger, because the field lines are closer together in that region.

What can you say about the field at point 1 compared with the field at point 2? -The field at point 1 is zero, because point 1 is not on a field line. -The field at point 1 is larger, because the field lines are closer together in that region. -The field at point 2 is larger, because point 2 is on a field line. -The field at point 1 is larger, because point 1 is not on a field line.

None of the above.

What happens to the electrons when they reach the lightbulb? The electrons are used up. The electrons are emitted as light. Fewer electrons leave the bulb than enter it. The electrons stay in the lightbulb. None of the above.

The resistance increases as temperature increases.

What happens to the resistance of most common metals as the temperature of the metal increases? -The resistance decreases as temperature increases. -The resistance increases as temperature increases. -Whether resistance increases or decreases as temperature increases depends on the type of metal. -The resistance remains constant as temperature increases.

the electrons already in the wire are instantly "pushed" by a voltage difference.

When a light switch is turned on, the light comes on immediately because -the lightbulb may be old with low resistance. It would take longer if the bulb were new and had high resistance. -the electricity bill is paid. The electric company can make it take longer when the bill is unpaid. -the electrons already in the wire are instantly "pushed" by a voltage difference. -the electrons coming from the power source move through the initially empty wires very fast.

-The magnitude of the net electric field at the center of the square is 0 N/C

When a point charge of +q is placed on one corner of a square, an electric field strength of 2 N/C is observed at the center of the square. Suppose three identical charges of +q are placed on the remaining three corners of the square. What is the magnitude of the net electric field at the center of the square? -The magnitude of the net electric field at the center of the square is 6 N/C. -The magnitude of the net electric field at the center of the square is 4 N/C. -The magnitude of the net electric field at the center of the square is 8 N/C. -The magnitude of the net electric field at the center of the square is 2 N/C. -The magnitude of the net electric field at the center of the square is 0 N/C

with the same brightness.

When connected to a battery, a lightbulb glows brightly. If the battery is reversed and reconnected to the bulb, the bulb will glow brighter. dimmer. with the same brightness. not at all.

Ohm's law is not obeyed in this case.

When you double the voltage across a certain material or device, you observe that the current increases by a factor of 3. What can you conclude? -This situation has nothing to do with Ohm's law. -Ohm's law is obeyed, because the current increases when V increases. -Ohm's law is not obeyed in this case.

The current is the same at all points.

Where in the circuit of (Figure 1) is the current the largest, (a), (b), (c), or (d)? (a) (b) (c) (d) The current is the same at all points.

next to a tall tree in a forest. in the middle of a grassy meadow. on a metal observation tower.

Which are the worst places to be safe during a lightning storm? Check three options that apply. inside a wooden building. next to a tall tree in a forest. in the middle of a grassy meadow. inside a metal car. on a metal observation tower.

Energy stored in the capacitor. Charge on the plates.

Which of the following do not affect capacitance? Check all that apply. Energy stored in the capacitor. Material between the plates. Area of the plates. Separation of the plates. Charge on the plates.

Ohm's law relates the current through a wire to the voltage across the wire.

Which of the following statements about Ohm's law is true? -Ohm's law holds for all materials. -Ohm's law is a fundamental law of physics. -Any material that obeys Ohm's law does so independently of temperature. -Ohm's law is valid for superconductors. -Ohm's law relates the current through a wire to the voltage across the wire.

-Electric field lines point away from positive charges and toward negative charges. -At every point in space, the electric field vector at that point is tangent to the electric field line through that point. -Electric field lines can never intersect.

Which of the following statements are true for electric field lines? Check all that apply. -Electric field lines point away from positive charges and toward negative charges. -Electric field lines are close together in regions of space where the magnitude the electric field is weak and are father apart where it is strong. -Electric field lines are continuous; they do not have a beginning or an ending. -At every point in space, the electric field vector at that point is tangent to the electric field line through that point. -Electric field lines can never intersect.

-Current is the total amount of charge that passes through a conductor's full cross section at any point per unit of time. -In order to maintain a steady flow of current in a conductor, a steady force must be maintained on the mobile charges.

Which of the following statements are true? Check all that apply. -By convention, the direction of a current is taken to be the direction of flow for negative charges. -When an electric field is applied to a conductor, the free electrons move only in the direction opposite the applied electric field. -Current is the total amount of charge that passes through a conductor's full cross section at any point per unit of time. -In order to maintain a steady flow of current in a conductor, a steady force must be maintained on the mobile charges. -In a circuit, current is delivered by the positive terminal of a battery, and it is used up by the time it returns to the negative terminal of the battery.

-Electric charge is conserved. -Electric charge is quantized. -Two negative charges repel each other. -A positive charge and a negative charge attract each other.

Which of the following statements are true? Check all that apply. -Electric charge is conserved. -Electric charge is quantized. -Two negative charges repel each other. -A positive charge and a negative charge attract each other. -A neutral object contains no charge. -Two positive charges attract each other.

Good conductors of electricity have larger conductivity values than insulators. The resistance of a conductor is proportional to the resistivity of the material of which the conductor is composed. A material that obeys Ohm's law reasonably well is called an ohmic conductor or a linear conductor.

Which of the following statements are true? Check all that apply. -Good conductors of electricity have larger conductivity values than insulators. -Semiconductors have resistivity values that are larger than those of insulators. -The resistance of a conductor is proportional to the resistivity of the material of which the conductor is composed. -A material that obeys Ohm's law reasonably well is called an ohmic conductor or a linear conductor. -The resistance of a conductor is proportional to the conductivity of the material of which the conductor is composed.

-The electric field between the plates of a parallel-plate capacitor is uniform. -A capacitor is a device that stores electric potential energy and electric charge. -The capacitance of a capacitor depends upon its structure.

Which of the following statements are true? Check all that apply. -The electric field between the plates of a parallel-plate capacitor is uniform. -A capacitor is a device that stores electric potential energy and electric charge. -A capacitor consists of a single sheet of a conducting material placed in contact with an insulating material. -The capacitance of a capacitor depends upon its structure.

-In a uniform electric field, the field lines are straight, parallel, and uniformly spaced. -The electric force acting on a point charge is proportional to the magnitude of the point charge. -Electric field lines near positive

Which of the following statements are true? Check all that apply. -The electric field created by a point charge is constant throughout space. -In a uniform electric field, the field lines are straight, parallel, and uniformly spaced. -Electric field lines near negative point charges circle clockwise. -The electric force acting on a point charge is proportional to the magnitude of the point charge. -Electric field lines near positive point charges radiate outward.

-Electric field lines and equipotential surfaces are always mutually perpendicular. -An equipotential surface is a three-dimensional surface on which the electric potential is the same at every point. -When all charges are at rest, the surface of a conductor is always an equipotential surface.

Which of the following statements are true? Check all that apply. -The potential energy of a test charge increases as it moves along an equipotential surface. -Electric field lines and equipotential surfaces are always mutually perpendicular. -An equipotential surface is a three-dimensional surface on which the electric potential is the same at every point. -The potential energy of a test charge decreases as it moves along an equipotential surface. -When all charges are at rest, the surface of a conductor is always an equipotential surface.

-If the potential throughout a particular region is constant, the field throughout that region must be zero.

Which of the following statements is valid? -If the field throughout a particular region is constant, the potential throughout that region must be zero. -If the potential at a particular point is zero, the field at that point must be zero. -If the field at a particular point is zero, the potential at that point must be zero. -If the potential throughout a particular region is constant, the field throughout that region must be zero.

-Decreasing the separation between the plates will increase the capacitance of a parallel-plate capacitor. -Increasing the area of the plates will increase the capacitance of a parallel-plate capacitor.

Which of the following will increase the capacitance of a parallel-plate capacitor? Check all that apply. -Decreasing the area of the plates will increase the capacitance of a parallel-plate capacitor. -Decreasing the separation between the plates will increase the capacitance of a parallel-plate capacitor. -Increasing the separation between the plates will increase the capacitance of a parallel-plate capacitor. -Increasing the area of the plates will increase the capacitance of a parallel-plate capacitor.

-Decreasing the cross-sectional area of the wire will increase the resistance of the wire. -Increasing the resistivity of the material the wire is composed of will increase the resistance of the wire. -Increasing the length of the wire will increase the resistance of the wire.

Which of the following will increase the resistance of a wire? Check all that apply. -Decreasing the cross-sectional area of the wire will increase the resistance of the wire. -Decreasing the length of the wire will increase the resistance of the wire. -Increasing the cross-sectional area of the wire will increase the resistance of the wire. -Increasing the resistivity of the material the wire is composed of will increase the resistance of the wire. -Decreasing the resistivity of the material the wire is composed of will increase the resistance of the wire. -Increasing the length of the wire will increase the resistance of the wire.

(d)

Which vector best represents the direction of the electric field at the fourth corner of the square due to the three charges shown in (Figure 1)? (a) (b) (c) (d) (e)