clicker questions chapter 23 and 24

Using Gauss' law, find the approximate magnitude of the electric field at the surface of a cube that has 0.10-m sides and a uniform volume charge density = 2.0 × 109 C/m3. a) 0.042 N/C b) 7.1 N/C c) 23 N/C d) 44 N/C e) 116 N/C

23 N/C

The end of a garden hose is enclosed in a mesh sphere of radius 4 cm. If the hose delivers five liters per minute, how much water flows through the sphere each minute? a) 0.0013 liters b) 0.67 liters c) 3.2 liters d) 5.0 liters e) 20 liters

5.0 liters

. Using Gauss' law, find the approximate magnitude of the electric field at the center of a circular face of a solid cylinder that has a length of 0.050-m, a radius of 0.020 m, and a uniform volume charge density = 2.0 × 109 C/m3. a) 0.42 N/C b) 11 N/C c) 23 N/C d) 33 N/C e) 76 N/C

11 N/C

A straight, copper wire has a length of 0.50 m and an excess charge of -1.0 × 105 C distributed uniformly along its length. Find the magnitude of the electric field at a point located 7.5 × 10-3 m from the midpoint of the wire. a) 1.9 × 1010 N/C b) 7.3 × 108 N/C c) 6.1 × 1013 N/C d) 1.5 × 106 N/C e) 4.8 × 107 N/C

4.8 × 107 N/C

A conducting shell with an outer radius of 2.5 cm and an inner radius of 1.5 cm has an excess charge of 1.5 × 107 C. What is the surface charge density on the inner wall of the shell? a) 1.5 × 109 C/m2 b) 2.9 × 1010 C/m2 c) 4.8 × 1010 C/m2 d) 8.5 × 109 C/m2 e) None of the above answers is correct.

None of the above answers is correct.

A large sheet of electrically insulating material has a uniform charge density . Let's compare the electric field produced by the insulating sheet with that produced by a thin metal (electrically conducting) slab with /2 charge density distributed on one large surface of the slab and /2 distributed over the surface on the opposite side. How does the electric field at a distance d from each surface compare? a) The electric field near the insulating sheet is four times that near the conducting slab. b) The electric field near the insulating sheet is twice that near the conducting slab. c) The electric field near the insulating sheet is the same as that near the conducting slab. d) The electric field near the insulating sheet is one half that near the conducting slab. e) The electric field near the insulating sheet is one fourth that near the conducting slab.

The electric field near the insulating sheet is the same as that near the conducting slab

Consider the equipotential lines shown in the box. The labeled cases indicate electric field line drawings. Which of these cases best matches the equipotential lines shown? a) 1 b) 2 c) 3 d) 4 e) None of these cases match the equipotential lines shown.

a) 1

Consider the equipotential lines shown in the box. The labeled cases indicate electric field line drawings. Which of these cases best matches the equipotential lines shown? a) 1 b) 2 c) 3 d) 4 e) None of these cases match the equipotential lines shown.

a) 1

A total charge of -6.50 µC is uniformly distributed within a sphere that has a radius of 0.150 m. What is the magnitude and direction of the electric field at 0.300 m from the surface of the sphere? a) 2.89 10^5 N/C, radially inward b) 9.38 105 N/C, radially outward c) 1.30 106 N/C, radially inward d) 6.49 105 N/C, radially outward e) 4.69 105 N/C, radially inward

a) 2.89 10^5 N/C, radially inward

Consider two conducting spheres with one having a larger radius than the other. Both spheres carry the same amount of excess charge. Which one of the following statements concerning the potential energy of the two spheres is true? a) The potential energy of the larger sphere is greater than that of the smaller sphere. b) The potential energy of the larger sphere is the same as that of the smaller sphere. c) The potential energy of the larger sphere is less than that of the smaller sphere.

a) The potential energy of the larger sphere is greater than that of the smaller sphere.

A uniform electric field is directed in the negative x direction. If you were to move a positive charge in the positive x direction, how would the total energy of the positive charge / electric field system change, if at all? a) The total energy of the system would increase. b) The total energy of the system would decrease. c) The total energy of the system would remain unchanged.

a) The total energy of the system would increase.

The drawing shows three point charges of equal magnitude, but one is positive (shown in blue) and two are negative (shown in yellow). Some of the equipotential lines surrounding these charges are shown and five are labeled using letters A, B, C, D, and E. What is the direction of the electric field at the location of the letter "D?" a) perpendicular to the equipotential line marked "D" and directed toward the negative charge closest to it b) parallel to the equipotential line marked "D" and directed toward the location of the letter "C" c) perpendicular to the equipotential line marked "D" and directed toward the location of the letter "A" d) toward the negative charge in the lower part of the drawing e) toward the positive charge

a) perpendicular to the equipotential line marked "D" and directed toward the negative charge closest to it

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 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

a) under all conditions

The a solid brass sphere of radius 3 cm is placed 0.5 m directly below a water faucet. The flow of water from the faucet is two liters per minute. How much water flows through the sphere each minute? a) zero liters b) 0.018 liters c) 0.09 liters d) 2 liters e) 6 liters

a) zero liters

. The drawing shows four points surrounding an electric dipole. Which one of the following expressions best ranks the electric potential at these four locations? a) 1 > 2 > 3 > 4 b) 1 > 2 = 4 > 3 c) 3 > 2 > 4 > 1 d) 3 > 2 = 4 > 1 e) 2 = 4 > 1 = 3

b) 1 > 2 = 4 > 3

. Consider the system shown in the drawing. A positive charge Q is placed at the center of a hollow conductor that was initially electrically neutral. The arrows are pointing to four locations: (1) a point in the conductor near the outer surface, (2) a point in the hollow space located halfway between the charge Q and the inner surface, (3) a point in the conductor halfway between the inner and outer surfaces, and (4) a point in the conductor near the inner surface. Which of the following choices best ranks the electric potentials at these four locations? a) 1 = 2 = 3 = 4 b) 2 > 1 = 3 = 4 c) 1 = 3 = 4 > 2 d) 1 > 4 > 3 > 2 e) 2 > 3 > 4 > 1

b) 2 > 1 = 3 = 4

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, even though there is nothing physical wrong with the array. What is the most likely cause of Joe's winter problem? a) Less sunlight reaches the Earth during the winter months. b) The sun is lower in the sky during the winter, so sunlight strikes the solar panels at an angle. c) The average temperature is much colder during the winter months. d) More sunlight is absorbed by the atmosphere during the winter months because the Sun is much lower in the sky. e) The Sun is not as bright during winter months as it is during the summer months.

b) The sun is lower in the sky during the winter, so sunlight strikes the solar panels at an angle.

Consider the four arrangements of three point charges. Rank the values of the total electric potential at point P in each case in descending order (with the largest first). a) VA > VD > VC > VB b) VC > VB > VD > VA c) VC > VD > VA > VB d) VB > VC > VB > VA e) VD > VB > VA > VC

b) VC > VB > VD > VA

A spherical shell has an outer radius of 0.10 m and an inner radius of 0.040 cm. Within the shell is a charge q = 2.0 × 109 C. What is the surface charge density on the outer surface of the shell? a) -2.0 × 10^-9 C/m2 b) -9.9 × 109 C/m2 c) -1.6 × 108 C/m2 d) -3.8 × 1010 C/m2 e) -8.0 × 108 C/m2

c) -1.6 × 108 C/m2

Which one of the following statements concerning electrostatic situations is false? a) No work is required to move a charge along an equipotential surface. b) If the electric potential with a region of space is zero volts, the electric field within that region must also be zero V/m. c) If a charge is moved along an equipotential surface, there is no component of the force acting along the charge's path. d) The electric field is always perpendicular to equipotential surfaces. e) The electric field is zero V/m everywhere inside a conductor

c) If a charge is moved along an equipotential surface, there is no component of the force acting along the charge's path.

Gauss' law may be written: . Which of the following statements concerning the charge q is true? a) The charge q is the sum of all charges. b) The charge q is the sum of all charges on the Gaussian surface. c) The charge q is the sum of all charges inside the Gaussian surface. d) The electric field due to q is zero inside the Gaussian surface. e) The charge q is the amount of charge present whenever the electric field is constant.

c) The charge q is the sum of all charges inside the Gaussian surface.

. Consider two conducting spheres with one having a larger radius than the other. Both spheres carry the same amount of excess charge. Which one of the following statements concerning the electric potential of the two spheres is true? a) The electric potential of the larger sphere is greater than that of the smaller sphere. b) The electric potential of the larger sphere is the same as that of the smaller sphere. c) The electric potential of the larger sphere is less than that of the smaller sphere.

c) The electric potential of the larger sphere is less than that of the smaller sphere.

Two point charges lie along the x axis. One charge, located at the origin, has a magnitude +2q. The other charge of unknown magnitude and sign is located at x = 5 units. If the electric potential at x = 4 units is equal to zero volts, what is the magnitude and sign of the second point charge? a) q/2 b) q/4 c) 2q d) +q/2 e) +2q

d) +q/2

The electric potential of an uncharged, spherical conductor with a radius of 0.1 m is 10 V. If the sphere is located in a region of space with no electric fields, what is the electric potential at a point located 2 m from the center of the sphere? a) zero volts b) 2.5 V c) 5 V d) 10 V e) 20 V

d) 10 V

A proton is moved from point B to point A in an electric field as shown. As a result of its movement, its potential increases to V. If three protons are moved from point B to A, how much will the electric potential of the protons increase? a) V/9 b) V/3 c) V d) 3V e) 9V

d) 3V

Two electrons are separated by a distance R. If the distance between the charges is increased to 2R, what happens to the total electric potential energy of the system? a) The total electric potential energy of the system would increase to four times its initial value. b) The total electric potential energy of the system would increase to two times its initial value. c) The total electric potential energy of the system would remain the same. d) The total electric potential energy of the system would decrease to one half its initial value. e) The total electric potential energy of the system would decrease to one fourth its initial value.

d) The total electric potential energy of the system would decrease to one half its initial value.

The electric potential energy for two positive charges of magnitude q and separated by a distance r is U1. What will the electric potential energy be if one of the charges is completely removed and replaced by a negative charge of the same magnitude? a) U2 = 2U1 b) U2 = U1 c) U2 = -U1 d) U2 = -2 U1

d) U2 = 2 U1

The drawing shows three point charges of equal magnitude, but one is positive (shown in blue) and two are negative (shown in yellow). Some of the equipotential lines surrounding these charges are shown and five are labeled using letters A, B, C, D, and E. At which of the labeled points will an electron have the greatest electric potential energy? a) A b) B c) C d) D e) E

d)D

Why is an electrostatic force considered a conservative force? a) Charged particles do not experience friction, which is a non-conservative force. b) The energy required to move a charged particle around a closed path is equal to zero joules. c) The work required to move a charged particle from one point to another does not depend upon the path taken. d) Answers (a) and (b) are both correct. e) Answers (b) and (c) are both correct.

e) Answers (b) and (c) are both correct.

. When you calculate the electric flux through a Gaussian surface, of what are you determining the flow through the surface? a) charge b) electric current c) electric energy d) electric field e) None of the above answers are correct.

e) None of the above answers are correct.

A positive charge is located at the origin. What is the direction of the electric potential of the positive charge? a) radially outward from the origin b) radially inward from the origin c) toward the positive x, y, and z directions d) toward the negative x, y, and z directions e) There is no direction since the electric potential is a scalar quantity.

e) There is no direction since the electric potential is a scalar quantity.