P6 LT2 - University Physics 14th ed summary of quiz part 2 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)?...