P6 - University Physics 14th ed summary of quiz PDF

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"A conducting sphere is charged up such that the potential on its surface is 100 V (relative to infinity). If the sphere's radius was twice as large, but the charge on the sphere is the same,what would be the potential on the surface relative to infinity?"1. "A parallel-platecapacitor is connected t...

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"A conducting sphere is charged up such that the potential on its surface is 100 V (relative to infinity). If the sphere's radius was twice as large, but the charge on the sphere is the same, what would be the potential on the surface relative to infinity?"1. "A parallel-plate

capacitor is connected to a battery and becomes fully charged. The capacitor is then disconnected, and the separation between the plates is increased in such a way that no charge leaks off. The energy stored in this capacitor has" INCREASED 2.

"Consider a uniform electric field of 50 N/C directed toward the east. If the voltage measured relative to ground at a given point in the field is 80 V, what is the voltage at a point 1.0 m directly south of that point?" 80V

3.

A 6.0-V battery maintains the electrical potential difference between two parallel metal plates separated by 1.0 mm. What is the electric field between the plates? 6000V/m

4.

"A small charged ball is accelerated from rest to a speed v by a 500 V potential difference. If the potential difference is changed to 2000 V, what will the new speed of the ball be?" 2v

5. The energy acquired by a particle carrying a charge equal to that on the electron as a result of moving through a potential difference of one volt is referred to as AN ELECTRON VOLT 6.

The absolute potential at a distance of 2.0 m from a negative point charge is -100 V. What is the absolute potential 4.0 m away from the same point charge? -50V

7.

"If a Cu2+ ion drops through a potential difference of 12 V, it will acquire a kinetic energy (in the absence of friction) of" 24.0 eV

8.

How will the capacitance of a parallel-plate capacitor change if the area of each plate is doubled and the distance between the plates is also doubled? It will remain the same

9.

How much work must be done by an external force to bring a 3.00 microcoulomb charge from infinity to a point 0.500 m from a 20.0 microcoulomb charge? 1.08J

10. The two conductors comprising a parallel-plate capacitor must be both positive. FALSE

11. Which of the following best describes electric potential energy?

The energy a

charge has due to its position relative to other charges.

12. The parallel plates of a 100 F capacitor are 1.0 m apart. What is their area (in m^2)? 1.13 x 10^13 13. The potential difference between two plates of a capacitor is referred to as the capacitance. 14. "Two parallel plates are charged to produce a potential difference of 50 V. If the separation between the plates is 0.050 m, what is the electric field between the plates?" 1000V/m 15. The potential of a negative charge is positive at any point around the charge FALSE 16. "The electric field between square the plates of a parallel-plate capacitor has magnitude E. The potential across the plates is maintained with constant voltage by a battery as they are pulled apart to twice their original separation, which is small compared to the dimensions of the plates. What is the now the magnitude of the electric field between the plates?" E/2 17. "The charge on the square plates of a parallel-plate capacitor is Q. The potential across the plates is maintained with constant voltage by a battery as they are pulled apart to twice their original separation, which is small compared to the dimensions of the plates. The amount of charge on the plates is now equal to ____." Q/2 18. A negative charge is moved from point A to point B along an equipotential surface. Which of the following statements must be true for this case? No work is required to move the negative charge from point A to point B. 19. "If the electrical potential in a region is constant, what must be the value of the electric field everywhere in that region?" ZERO 20. "Each plate of an air-filled parallel-plate air capacitor has an area of 0.0040 m^2, and the separation of the plates is 0.080 mm. An electric field of 5.3 × 10^6 V/m is present between the plates. What is the energy density between the plates? " 124 J/m^3 21. "In a certain region, the electric potential due to a charge distribution is given by the equation V(x,y) = 2xy - x^2 - y, where x and y are measured in meters and V is in volts. At which point is the electric field equal to zero?" "x = 0.5 m, y = 0.5 m"

22. Four equal +6.00-?C point charges are placed at the corners of a square 2.00 m on each side. What is the electric potential (relative to infinity) due to these charges at the center of this square? 153 kV 23. How much work (in J) is needed to move a charged particle by 7.3 mm with a 34000 N of force? 248.2 25. Consider that the earth and the atmosphere forms a parallel plates of charges. Where the electric field in the region is 120 N/C pointing downward. If a particle whose charge is -1.75 C is placed 10 m above the ground, what would be its electric potential energy (in J)? (Hint: See p. 753 eqn. 23.5. Note that the e-field to use is just its magnitude.) -2100 26. The electric potential difference , also called voltage, is expressed in terms of the electric field as follows where, a is the initial position and b is the final position. If an electric field in a region in space is defined aswhere is just a constant without an arbitrary value. What is the electric potential difference from position 0 to R? 2/3br3 dami to bwisit iba iba pero magegets niyo naman paano 28. Consider that the earth and the atmosphere forms a parallel plates of charges. Where the electric field in the region is 790 N/C pointing downward. If a particle whose charge is -1 C is placed 10 m above the ground, what would be its electric potential energy (in J)? (Hint: See p. 753 eqn. 23.5. Note that the e-field to use is just its magnitude.) -7900 29. "Suppose you have two point charges of opposite sign. As you move them farther and farther apart, the potential energy of this system relative to infinity _____." INCREASES 30. "A conducting sphere is charged up such that the potential on its surface is 100 V (relative to infinity). If the sphere's radius was twice as large, but the charge on the sphere is the same, what would be the potential on the surface relative to infinity?" 50 V 31. "An extremely long thin wire carries a uniform linear charge density of 358 nC/m. Find the potential difference between points 5.0 m and 6.0 m from the wire, provided they are not near either end of the wire." 1.2kV 32. How much work (in J) is needed to move a proton by 2 cm with a 10000 N of electric force? 200

33. Doubling the capacitance of a capacitor holding a constant charge causes the energy

stored in that capacitor to decrease to 1/4 34. "A battery charges a parallel-plate capacitor fully and then is removed. The plates are immediately pulled apart. (With the battery disconnected, the amount of charge on the plates remains constant.) What happens to the potential difference between the plates as they are being separated?" IT INCREASES 35. "If the electric field between two parallel plates of a capacitor is weakened, the capacitance ____________." REMAINS THE SAME 36. The charge of a capacitor and the voltage applied to it are directly proportional. TRUE 37. A parallel-plate capacitor has square plates of edge length 0.10 m separated by 0.001 m. Calculate the capacitance in picofarad. 89pF 38. Two protons are 3.35 x 10^-15 m apart. What is the electric potential energy of the system? 6.9 x 10^-14 J 39. "A proton, initially at rest, is accelerated through an electric potential difference of 500

V. What is the speed of the proton?" 3.1x105 m/s 40. Electric dipoles always consist of two charges that are EQUAL IN MAGNITUDE,

OPPOSITE IN SIGN 41. A proton moves 0.10 m along the direction of an electric field of magnitude 3.0 V/m. What is the change in kinetic energy of the proton? 4.8x10-20 J 42. What is the potential at a distance of 5.0 ? 10-10 m from a nucleus of charge +50e?

was 140V

43. "Two parallel conducting plates are separated by 1.00 mm and carry equal but opposite surface charge densities. If the potential difference between them is 2.0 V, what is the magnitude of the surface charge density on each plate?" 18 44. What is the electric potential 0.0529 nanometer from a proton? 27.2 45. It takes 50 J of energy to move 10 C of charge from point 1 to point 2. What is the potential difference between the two points? 5V 46. Suppose 10.0 kV is applied on a 3.54-nF parallel-plate capacitor. How many microcoulombs are in each plate? 35.4 47. __________ charges tend to go to regions of __________ potential. Negative; higher

48. One volt is equivalent to one coulomb per joule FALSE 49. How much work (in J) is needed to move a proton by 4 m with a force of 2000 N? 8000 50.

50. "A small charged ball is accelerated from rest to a speed v by a 500 V potential difference. If thepotential difference is changed to 2000 V, what will the new speed of the ball be?" 2v

52. The work needed to move a charge between two points at the same electric potential is

ZERO 53. A conducting sphere contains positive charge distributed uniformly over its surface. Which statements about the potential due to this sphere are true? All potentials are measured relative to infinity. The potential at the center of the sphere is the same as the potential at the surface 54. Which two quantities are equivalent? electric potential difference and voltage 55. "A 1.0 ?F capacitor has a potential difference of 6.0 V applied across its plates. If the

potential difference across its plates is increased to 8.0 V, how much ADDITIONAL energy does the capacitor store?" 14 56. Consider that the earth and the atmosphere forms a parallel plates of charges. Where the electric field in the region is 790 N/C pointing downward. If a particle whose charge is 1 C is placed 10 m above the ground, what would be its electric potential energy (in J)? 7900 57. How much work (in J) is needed to displace a charged particle by 1.74 mm with a 843000 N of electric force? CONVERT NIYO YUNG 1.74 mm to m then multiply to 843000 1466.82 58. A dielectric material such as paper is placed between the plates of a capacitor. What happens to the capacitance? Becomes larger 59. "If the electric field is zero everywhere inside a region of space, the potential must also be zero in that region." False 60. The potential energy of a system of two positive charges decreases as the distance between the charges increases. TRUE 61. "Four charges of equal charge +q are placed at the corners of a rectangle of sides a and b. What is the potential at the center of the rectangle if q = 2.0 mC, a = 3.0 cm, and b = 4.0 cm?" 2.9x106V

62. Several electrons are placed on a hollow conducting sphere. They - become uniformly distributed on the sphere's outer surface. 63.Consider that the earth and the atmosphere forms a parallel plates of charges. Where the electric field in the region is 631 N/C pointing downward. If a particle whose charge is -0.75 C is placed 1.25 m above the ground, what would be its electric potential energy (in J)? (Hint: See p. 753 eqn. 23.5. Note that the e-field to use is just its magnitude.)

64. Consider that the earth and the atmosphere forms a parallel plates of charges. Where the electric field in the region is 301 N/C pointing downward. If a particle whose charge is 0.75 C is placed 1.25 m above the ground, what would be its electric potential energy (in J)?

1. law is an equation that states that the electric flux in a closed region in space is equal to the enclosed charge over the permittivity of free space. GAUSS’S 2. The product of the electric field and area is called the electric FLUX 3. is a region in space produced by a charge that carries with it a force. It is mathematically defined as force over charge. - ELECTRIC FIELD 4. The SI unit for the electric charge is ____________ - COULOMB 5. It is _________________ (true/false) that the direction of the electric field from a negative point 6. 7. 8. 9. 10. 11. 12.

charge is towards it. - TRUE The SI unit for electric field is ___________________ N/C If a Gaussian surface encloses a space that contains 1C positive charge and two 0.5C negative charge, the electric flux in that Gaussian surface is - zero Because electric field has direction then therefore it is an example of ____________ quantity. VECTOR If a Gaussian surface encloses a space that has no charge in it, the electric flux in that Gaussian surface is _______ - zero It is _________________ (true/false) that Gauss's law provides a shortcut to direct integration if the Gaussian surface is symmetric - TRUE Because electric flux does not indicate direction in space then therefore it is an example of scalar If a Gaussian surface encloses a space that contains a positive and negative charge of the same magnitude, the electric flux in that Gaussian surface is _______ZERO

13. Three identical point charges of 2.0 µC are placed on the x-axis. The first charge is at

the origin, the second to the right at x = 50 cm, and the third is at the 100 cm mark. What are the magnitude and direction of the electrostatic force which acts on the charge at the origin? - 0.18 N Left 14. Two closely spaced metal sheets of the same area have equal but opposite charges. Both sheets are horizontally aligned in space with the top sheet having positive surface charge density while the sheet with negative charge density is at the bottom. What is the electric field in the region at the top of the positively charged sheet? - zero 15. Why is a spherical Gaussian surface appropriate when calculating the electric field of a point charge?

The normal vector at any point on the sphere is parallel to the electric field of the point charge.

16. Three 3.0 µC charges are at the three corners of an square of side 0.50 m. The last corner is occupied by a -3.0 µC charge. Find the electric field at the center of the square. - 4.3x105 N/C 17. Two point charges q = 4.2 nC (negtive) and Q = 4.2 nC (positive) are separated by distance 3.5 mm. What is their electric dipole moment? 1.7 x 10^ -3 Cm (from q to Q) 18. A piece of plastic has a net charge of +2.00 µC. How many more protons than electrons does this piece of plastic have? 1.25x1013

19. An infinitely long nonconducting cylinder of radius R = 2.00 cm carries a uniform volume

charge density of 18.0 micro-Coulomb/cubic meter. Calculate the electric field at distance r = 1.00 cm from the axis of the cylinder. 10.2 x 10^3 N/C 20. if a conductor is in electrostatic equilibrium near an electric charge - The electric field on the surface of the conductor is perpendicular to the surface 21. "Two charges q1 = 2.0 nC and q2 = 9.0 nC are placed at (x = 2.0 m, y = 0) and (x = 0, y

= 8.0 m) respectively. What is the magnitude of the net electric field at the origin?" -1.3 x 10^18N/C

22. Which of the following does not affect electric flux? - shape of the source charge 23. If the electric flux through a Gaussian surface enclosing an unknown charge is -1.81 x 10^-8 N?m^2/C. What is the electric flux through the Gaussian surface if it encloses 1000 of these unknown charges? - 1.81 x 10^-5 N?m^2/C

24. Two charged objects are separated by a distance d. The first charge is larger in magnitude than the second charge. - The charges exert forces on each other equal in magnitude and opposite in direction. 25. What does it mean if the electric flux through a closed surface is negative? - The charge inside the closed surface is negative. 26. "If 3 N force is exerted on a positive charge due to an electric field of 5 N/C, what is the

value of the charge?" 0.6C 27. What is the electric field 7.0 m from a point charge q = 8.0 nC? 1.47 N/C

28. An infinitely long nonconducting cylinder of radius R = 2.00 cm carries a uniform volume charge density of 18.0 micro-Coulomb/cubic meter. Calculate the electric field at distance r = 1.00 cm from the axis of the cylinder. 10.2 x 10^3 N/C 29. "Two identical small charged spheres are a certain distance apart, and each one initially experiences an electrostatic force of magnitude F due to the other. With time, charge gradually leaks off of both spheres. When each of the spheres has lost half its initial charge, the magnitude of the electrostatic force will be" ¼ F 30. Where do charges on a conductor reside under electrostastic conditions? On the surface 31. What must be the charge of a 1.46 g particle for it to remain stationary when placed in a downward directed electric field of magnitude N/C? 21 micro-Coulomb (negative charge) 32. Three point charges are located at the following positions: Q1 = 2.00 µC at x = 1.00 m; Q2 = 3.00 µC at x = 0; Q3 = -5.00 µC at x = -1.00 m. What is the magnitude of the force on the 3.00-µC charge? - 5.40x10-2 N 33. Suppose a charge -Q is located 24 units to the left of the origin. Where should another charge +Q be placed so that the net electric field at the origin is zero? - 24 units right to the origin 34. A 5.0-C charge is 10 m from a small test charge. What is the magnitude of the electric field at the location of the test charge? 4.5x108 N/C 35. Consider a square which is 1.0 m on a side. Charges are placed at the corners of the square as follows: +4.0 µC at (0, 0); +4.0 µC at (1, 1); +3.0 µC at (1, 0); -3.0 µC at (0, 1). What is the magnitude of the electric field at the square's center? 1.1 ×105N/C 36. A spherical conducting sphere of radius R = 10 cm has total excess charge Q. What is the electric field inside the sphere? zero 37. Consider a spherical Gaussian surface of radius R centered at the origin. A charge Q is placed inside the sphere. -anywhere 38. If the electric field through a disk is doubled, how will the electric flux change? - The electric flux will be doubled since electric flux is directly proportional to the electric field. 39. "A non-conducting sphere of radius R = 7.0 cm carries a charge Q = 4.0 mC distributed

uniformly throughout its volume. At what distance, measured from the center of the

sphere, does the electric field reach a value equal to half its maximum value?"3.5 and 9.9 40. An insulating sphere of radius R has a positive charge. At which region is the electric field at a maximum? r=R 41. It is _________________ (true/false) that the direction of the electric field from a positive point charge is inward and outward. false 42. A S pherical conducting sphere of radius R = 10 cm has total excess charge Q. What is

the electric field outside the sphere? - kQ/r^2 43. What is the direction of the electric field of a positive point charge? - radially outward 44. If a solid metal sphere and a hollow metal sphere of equal diameters are each given the same charge, the electric field (E) midway between the center and the surface is - zero for both 45. Two charges q1 = 2.0 nC and q2 = 9.0 nC are placed at (x = 2.0 m, y = 0) and (x = 0, y = 8.0 m) respectively. What is the magnitude of the net electric field at the origin? - 1.26 x 10^18

46. Consider two closely spaced and oppositely charged parallel metal plates. The plates are square with sides of length L and carry charges Q and -Q on their facing surfaces. What is the magnitude of the electric field in the region between the plates? Q/(epsilon naught)L^2

47. Which of the following is not always true about electric field lines?

Electric field lines are directed from positive to negative charge.

48. The normal vector of a disk (r = 10 cm) is parallel to a uniform electric field (E = 2.0 x 10^3 N/C). What is the flux through the disk? 49. It is _________________ (true/false) that the direction of the electric field from a positive point charge is towards it. false

50. At twice the distance from a point charge, the strength of the electric field is one-fourth its original value.

51. A spherical, non-conducting shell of inner radius = 10 cm (r1) and outer radius = 15 cm (r2) carries a total charge Q = 15 ?C dis...