3. As shown in the diagram below, a charged rod is held near, but not touching, a neutral electroscope.

Transcription

1 1. As a positively charged rod is brought near to but not allowed to touch the knob of an uncharged electroscope, the leaves will diverge because negative charges are transferred from the electroscope to the rod negative charges are attracted to the knob of the electroscope positive charges are repelled to the leaves of the electroscope positive charges are transferred from the rod to the electroscope 2. When an object is brought near the knob of a positively charged electroscope, the leaves of the electroscope initially diverge. The charge on the object must be zero must be negative must be positive cannot be determined 5. When a rod is brought near a neutral electroscope, the leaves diverge. Which statement best describes the charge on the rod? It must be positive. It must be negative. It may be neutral. It may be positive or negative. 6. A charged electroscope can detect positive charge, only negative charge, only either positive or negative charge neither positive nor negative charge 7. In the diagram below, a cloth is brought near, but does not touch a neutral electroscope. The electroscope leaves separate. What charge, if any, does the cloth have? 3. As shown in the diagram below, a charged rod is held near, but not touching, a neutral electroscope. The charge on the knob is positive and the leaves are positive positive and the leaves are negative negative and the leaves are positive negative and the leaves are negative 4. Which diagram best represents the charge distribution on a neutral electroscope when a negatively charged rod is held near it? a positive charge an unknown charge a negative charge no charge 8. An electroscope is a device with a metal knob, a metal stem, and freely hanging metal leaves used to detect charges. The diagram below shows a positively charged leaf electroscope. As a positively charged glass rod is brought near the knob of the electroscope, the separation of the electroscope leaves will decrease remain the same increase 9. The coulomb is a unit of resistance charge power force

2 10. A positively charged rod is held near the knob of a neutral electroscope. Which diagram best represents the distribution of charge on the electroscope? 12. When a positively charged body touches a neutral body, the neutral body will gain protons gain electrons lose protons lose electrons 13. Which diagram best illustrates a neutral electroscope being charged by conduction? 14. As shown in the diagram below, a neutral pith ball suspended on a string is attracted to a positively charged rod. During contact with the rod, the pith ball loses electrons loses protons gains electrons gains protons 15. A positively charged object was used to give an electroscope a negative charge. The electroscope was charged by contact induction conduction reduction 11. Negatively charged rod A is used to charge rod B by induction. Object C is then charged by direct contact with rod B. The charge on object C is neutral positive negative not be able to be determined 16. If an uncharged electroscope is touched with a neutral object, the separation of the leaves of the electroscope will decrease remain the same increase 17. A device commonly used to detect the presence of a static electric charge is a galvanometer a compass a voltmeter an electroscope

3 18. Which procedure will give an electroscope a positive charge? touching the electroscope with a neutral object bringing a positively charged object near the electroscope touching the electroscope with a negatively charged object touching the electroscope with a positively charged object 19. Which diagram shows an electroscope that has been charged by induction using a positive charging object? Base your answers to questions 26 and 27 on the diagram below which shows two identical metal spheres. Sphere A has a charge of +12 coulombs and sphere B is a neutral sphere. 26. When spheres A and B are in contact, the total charge of the system is neutral +12 C +6 C +24 C 27. After spheres A and B are separated, which graph best represents the relationship of the force between the spheres and their separation? 20. A glass rod becomes positively charged when it is rubbed with silk. This net positive charge accumulates because the glass rod gains electrons loses electrons gains protons loses protons 21. When a neutral metal sphere is charged by contact with a positively charged glass rod, the sphere loses electrons loses protons gains electrons gains protons 22. A positively charged body must have an excess of neutrons a deficiency of protons an excess of electrons a deficiency of electrons 23. When a rubber rod is rubbed with fur, the rod becomes negatively charged due to the transfer of electrons to the fur electrons to the rod protons to the fur protons to the rod 24. After a neutral object loses 2 electrons, it will have a net charge of 2 elementary charges +2 elementary charges elementary charge elementary charge 25. A rod and a piece of cloth are rubbed together. If the rod acquires a charge of coulomb, the cloth acquires a charge of. 0 C C C C 28. Two neutral materials are rubbed together and there is a transfer of electrical charge from one material to the other. The net electrical charge for the system increases as electrons are transferred increases as protons are transferred remains constant as electrons are transferred remains constant as protons are transferred 29. When a plastic rod is rubbed with wool, the wool acquires a positive charge because electrons are transferred from the wool to the rod protons are transferred from the wool to the rod electrons are transferred from the rod to the wool protons are transferred from the rod to the wool 30. Sphere A carries a charge of +2 coulombs and an identical sphere B is neutral. If the spheres touch one another and then are separated, the charge on sphere B would be +1 C 0 C +2 C +4 C 31. Two objects, A and B are rubbed together. If object A acquires an excess of 100 electrons object B must have gained 100 electrons lost 100 electrons gained 100 protons lost 100 protons

4 Base your answers to questions 32 through 34 on the diagram below which represents a system consisting of two charged metal spheres with equal radii. 32. If the two spheres were touched together and then separated, the charge on sphere A would be C C C C 33. If spheres A and B, as represented in the diagram, were touched together and then separated, the net charge on the two spheres would decrease remain the same increase 34. What is the magnitude of the electrostatic force exerted on sphere A? N N 120 N 10. N 35. Which magnitude of charge could not be found on an object? C C C C 36. Which electric charge is possible? C C C C 37. What is the charge of a proton? C C C C 38. A sphere has a net excess charge of 4.8 x coulomb. The sphere must have an excess of 1 electron 3 electrons 1 proton 3 protons 39. Compared to the charge on a proton, the charge on an electron has the opposite sign and a smaller magnitude opposite sign and same magnitude same sign and a smaller magnitude same sign and the same magnitude 40. An alpha particle consists of two protons and two neutrons. The alpha particle's charge of +2 elementary charges is equivalent to C C C C 41. An electrically neutral object can be attracted by a positively charged object because like charges repel each other the charges on a neutral body can be redistributed the neutral body becomes charged by contact the net charge in a closed system varies 42. An uncharged metal sphere is placed midway between spheres A and B represented in the diagram below. Which diagram best represents the arrangement of the charges in the uncharged sphere? 43. If a positively charged rod touches a neutral metal sphere, the number of electrons on the rod will decrease remain the same increase 44. An object with + 10 elementary charges is grounded and becomes neutral. What is the best explanation for this occurrence? The object gained 10 electrons from the ground. The object lost 10 electrons to the ground The object gained 10 protons from the ground. The object lost 10 protons to the ground. 45. A volt is defined as a joule/coulomb coulomb/second joule/second joule-second/coulomb

5 46. The diagram below shows four charged metal spheres suspended by strings. The charge of each sphere is indicated. 50. An inflated balloon which has been rubbed against a person's hair is touched to a neutral wall and remains attracted to it. Which diagram best represents the charge distribution on the balloon and wall? If spheres A, B, C, and D simultaneously come into contact, the net charge on the four spheres will be + 1 C + 3 C + 2 C + 4 C 47. The diagram below shows the initial charge and position of three identical metal spheres, X, Y, and Z, which have been placed on insulating stands. 51. In the diagram below a neutral pith ball is suspended on a string. A positively charged rod approaches the pith ball. All three spheres are simultaneously brought into contact with each other and then returned to their original positions. Which statement best describes the charge of the spheres after this procedure is completed? All the spheres are neutral. Each sphere has a net charge of +4 x 10 6 coulomb. Each sphere retains the same charge that it had originally. Sphere Y has a greater charge than spheres X or Z. 48. A neutral rubber rod is rubbed with fur and acquires a charge of coulomb. The charge on the fur is C C C C 49. An electric force F exists between two charged spheres. If the quantity of charge on each sphere is doubled, the electric-force between the two spheres will be equal to F 2 2F 3F 4F The ball will first move toward A C B D 52. A balloon is rubbed against a student s hair and then touched to a wall. The balloon sticks to the wall due to electrostatic forces between the particles of the balloon magnetic forces between the particles of the wall electrostatic forces between the particles of the balloon and the particles of the wall magnetic forces between the particles of the balloon and the particles of the wall

6 53. Two electrically neutral metal spheres, A and B, on insulating stands are placed in contact with each other. A negatively charged rod is brought near, but does not touch the spheres, as shown in the diagram below. 57. The diagram below shows three neutral metal spheres, x, y, and z, in contact and on insulating stands. How are the spheres now charged? A is positive and B is positive. A is positive and B is negative. A is negative and B is positive. A is negative and B is negative. Which diagram best represents the charge distribution on the spheres when a positively charged rod is brought near sphere x, but does not touch it? 54. Base your answer to the following question on the information and diagram below. Two conducting spheres, A and B, are separated by a distance of 2 meters between centers. Sphere A has a charge of coulomb, and sphere B has a charge of coulomb. The force that these two spheres exert upon each other is N N N N 55. Two charges that are 2 meters apart repel each other with a force of Newton. If the distance between the charges is decreased to 1 meter, the force of repulsion will be N N N N 56. An electrostatic force of magnitude F exists between two metal spheres having identical charge q. The distance between their centers is r. Which combination of changes would produce no change in the electrostatic force between the spheres? doubling q on one sphere while doubling r doubling q on both spheres while doubling r doubling q on one sphere while halving r doubling q on both spheres while halving r 58. If the distance separating an electron and a proton is halved, the magnitude of the electrostatic force between these charged particles will be unchanged quartered doubled quadrupled

7 59. The diagram shows three small metal spheres with different charges. Base your answers to questions 62 and 63 on the diagram below which represents two small charged spheres, A and B, 3 meters apart. Each sphere has a charge of C. Compared to the force between spheres A and B, the force between spheres B and C is one-quarter as great one-half as great twice as great four times as great 60. The diagram represents two charges, q 1 and q 2, separated by a distance d. 62. If another small sphere with a charge of +2.0 x 10 6 C is placed at point y, the net force on this sphere will be 0 N 80. N 40. N 240 N 63. If a positive charge is placed at point x, the direction of the net force on the charge will be into the page toward the left out of the page toward the right 64. The diagram below shows two metal spheres suspended by strings and separated by a distance of 3.0 meters. The charge on sphere A is coulomb and the charge on sphere B is coulomb. Which change would produce the greatest increase in the electrical force between the two charges? doubling charge q l, only doubling d, only doubling d and charge q l, only doubling d and charges q 1 and q An electron is located 1.0 meter from a +2.0-coulomb charge, as shown in the diagram below. Which statement best describes the electrical force between the spheres? It has a magnitude of 15 N and is repulsive. It has a magnitude of 45 N and is repulsive. It has a magnitude of 15 N and is attractive. It has a magnitude of 45 N and is attractive. 65. The electrostatic force of attraction between two small spheres that are 1.0 meter apart is F. If the distance between the spheres is decreased to 0.5 meter, the electrostatic force will then be F/2 F/4 2F 4F The electrostatic force acting on the electron is directed toward point A C B D 66. The electrostatic force between two positive point charges is F when the charges are 0.1 meter apart. When these point charges are placed 0.05 meter apart, the electrostatic force between them is 4F, and attracting 4F, and repelling F, and attracting F, and repelling

8 67. If the charge on each of two small spheres a fixed distance apart is doubled, the force of attraction between the spheres will be quartered halved doubled quadrupled 68. Which graph best represents the relationship between the magnitude of the electric force between two identical spheres possesing +1.0 coulomb of charge and 1.0 coulombs of charge respectivly, as well as the distance between them? 71. Electrostatic force F exists between two point charges. If the distance between the charges is tripled, the force between the charges will be F 9 F 3 3F 9F 72. The diagram below shows two negatively charged balloons suspended from nonconducting strings being held by a student. 69. The diagram below shows two metal spheres charged to coulomb and coulomb, respectively, on insulating stands separated by a distance of 0.10 meter. What occurs as the student brings the balloons closer to each other without allowing them to touch? The magnitude of the electrostatic force between the balloons decreases, and they attract each other. The magnitude of the electrostatic force between the balloons decreases, and they repel each other. The magnitude of the electrostatic force between the balloons increases, and they attract each other. The magnitude of the electrostatic force between the balloons increases, and they repel each other. 73. Which diagram best represents the electric field surrounding a positive point charge? The spheres are touched together and then returned to their original positions. As a result, the magnitude of the electrostatic force between the spheres changes from 2.7 N to 1.4 N 3.6 N 1.8 N 14 N 70. If the charge on each of two small charged metal spheres is doubled and the distance between the spheres remains fixed, the magnitude of the electric force between the spheres will be the same one-half as great two times as great four times as great 74. Two protons are located one meter apart. Compared to the gravitational force of attraction between the two protons, the electrostatic force between the protons is stronger and repulsive stronger and attractive weaker and repulsive weaker and attractive 75. The work required to move 2 coulombs of charge through a potential difference of 5 volts is 10 J 25 J 2 J 50 J

9 76. In the diagram below, A is a point near a positively charged sphere. 79. The diagram below shows the arrangement of three charged hollow metal spheres, A, B, and C. The arrows indicate the direction of the electric forces acting between the spheres. At least two of the spheres are positively charged. Which vector best represents the direction of the electric field at point A? Which sphere, if any, could be negatively charged? sphere A sphere C sphere B no sphere 77. Which diagram best represents the electric field around a negatively charged conducting sphere? 80. Base your answer to the following question on the diagram below which represents two small, charged conducting spheres, identical in size, located 2.00 meters apart. Which diagram best represents the electric field between the two spheres? 78. The diagram below shows the electric field in the vicinity of two charged conducting spheres, A and B. 81. Two equal positive point charges, A and B are positioned as shown below. What is the static electric charge on each of the conducting spheres? A is negative and B is positive. A is positive and B is negative. Both A and B are positive. Both A and B are negative. At which location is the electric field intensity due to these two charges equal to zero? A X B Y

10 82. Base your answer to the following question on the diagram below which represents two charged spheres, X and Y. 85. In the diagram below, two positively charged spheres, A and B, of masses m A and m B are located a distance d apart. Which arrow best represents the direction of the electric field at point A? Which diagram best represents the directions of the gravitational force, F g, and the electrostatic force, F e, acting on sphere A due to the mass and charge of sphere B? [Vectors are not drawn to scale.] 83. The diagram below shows two identical metal spheres, A and B, separated by distance d. Each sphere has mass m and possesses charge q. Which diagram best represents the electrostatic force F e and the gravitational force F g acting on sphere B due to sphere A? 86. Two positively charged masses are separated by a distance, r. Which statement best describes the gravitational and electrostatic forces between the two masses? Both forces are attractive. Both forces are repulsive. The gravitational force is repulsive and the electrostatic force is attractive. The gravitational force is attractive and the electrostatic force is repulsive. 84. A proton and an electron traveling with the same velocity enter a uniform electric field. Compared to the acceleration of the proton, the acceleration of the electron is less, and in the same direction less, but in the opposite direction greater, and in the same direction greater, but in the opposite direction 87. An electron is located between a pair of oppositely charged parallel plates. As the electron approaches the positive plate, the kinetic energy of the electron decreases remains the same increases

11 88. Two parallel aluminum plates are connected to a source of potential as shown in the diagram. 94. Base your answer to the following question on the diagram below which represents an electron being projected between two oppositely charged parallel plates. The electric field strength between the two plates is constant between the plates except near the edges zero midway between the plates maximum near the positively charged plate maximum midway between the plates Base your answers to questions 89 through 91 on the diagram below which represents a voltage source connected to two large, parallel metal plates. The electric field intensity between the plates is Newtons per coulomb. As the electron moves through the electric field, the magnitude of the electric force on the electron decreases remains the same increases Base your answers to questions 95 through 97 on the diagram below which shows two parallel metal plates A and B connected to a voltage source. 89. As a proton moves from A to B to C, the electric force on the proton decreases remains the same increases 90. What is the potential difference of the source? V V V V 91. What would be the magnitude of the electric force on a proton at point A? N N 0 N N 92. An electrostatic force of 20. Newtons is exerted on a charge of coulomb at point P in an electric field. The magnitude of the electric field intensity at P is N/C 1.6 N/C 20. N/C N/C 93. Which quantity and unit are correctly paired? resistivity and Þ/m potential difference and ev current and C s electric field strength and N C 95. What is the electric field intensity between the two plates? 400. N/C 625 N/C 500. N/C 4,000 N/C 96. If only the original source voltage is increased, the electric field intensity between the plates will decrease remain the same increase 97. If only the distance between the plates is increased, the electric field intensity between the plates will decrease remain the same increase 98. What is the magnitude of the electric field intensity at a point in the field where an electron experiences a 1.0- newton force? 10 N/C N/C N/C N/C

12 99. Base your answer to the following question on the diagram below which represents two large parallel conducting plates charged to a potential of 10. volts. The plates are separated by a distance of meter The diagram below shows a point, P, located midway between two oppositely charged parallel plates. The direction of the electric field at point P is toward point A C B D 100. Base your answer to the following question on the information and diagram below. Two parallel plates separated by a distance of meter are charged to a potential difference of 12 volts. An alpha particle with a charge of +2 elementary charges is located at point P in the region between the plates If an electron is introduced at point P, the electron will travel at constant speed toward the positively charged plate travel at constant speed toward the negatively charged plate accelerate toward the positively charged plate accelerate toward the negatively charged plate 103. An electron placed between oppositely charged parallel plates A and B moves toward plate A, as represented in the diagram below The electric field between the plates will cause the alpha particle, starting from rest at point P, to accelerate toward the positive plate accelerate toward the negative plate move at constant speed toward the positive plate move at constant speed toward the negative plate 101. Identical charges A, B, and C are located between two oppositely charged parallel plates, as shown in the diagram below. What is the direction of the electric field between the plates? toward plate A into the page toward plate B out of the page 104. Base your answer to the following question on the diagram below which represents an electron entering the region between two oppositely charged parallel plates. The magnitude of the force exerted on the charges by the electric field between the plates is least on A and greatest on C greatest on A and least on C the same on A and C, but less on B the same for A, B, and C In which direction will the electron be deflected by the electric field? toward the bottom of the page toward the top of the page into the page out of the page 105. The work required to move a charge of 3.0 coulombs through a potential difference of equal to 12 volts is 0.25 joule 36 joules 9 joules 4.0 joules

13 106. Two plastic rods, A and B. each possess a net negative charge of 1.0 x 10 3 coulomb. The rods and a positively charged sphere are positioned as shown below Base your answer to the following question on the diagram below which shows two large parallel metal plates connected to a source of electric potential. The plates are meter apart and the potential difference across the plates is 100 volts. Which vector best represents the resultant electrostatic force on the sphere? As an electron moves from plate B toward plate A, the electric force on the electron decreases remains the same increases Base your answers to questions 111 and 112 on the accompanying diagram which represents two large parallel plates which are oppositely charged. A, B, and C are reference points A positive test charge is placed between an electron, e, and a proton, p, as shown in the diagram below. When the test charge is released, it will move toward A C B D 108. What is the magnitude of the electrostatic force experienced by one elementary charge at a point in an electric field where the electric field intensity is Newtons per coulomb? N N N N 109. If 4 joules of work are required to move 2 coulombs of charge through a 6-ohm resistor, the potential difference across the resistor is 1 V 6 V 2 V 8 V 111. If an electron moves from point A to point B, the electron's electric potential energy will decrease remain the same increase 112. If an electron is moved from point A to point C, the potential energy of the electron will decrease remain the same increase 113. The two large metal plates shown in the diagram are charged to a potential difference of 100 volts. How much work is needed to move l coulomb of negative charge from point A to point B? 1 J 1 ev 100 J 100 ev

14 114. If 6.0 joules of work is done to move 2.0 coulombs of charge from point A to point B. what is the electric potential difference between points A and B? 6.0 V 3.0 V 0.33 V 12 V 117. The graph below shows the relationship between the work done on a charged body in an electric field and the net charge on the body An electrical potential of one joule per coulomb is equal to one coulomb one ohm one ampere one volt 116. Moving 2.0 coulombs of charge a distance of 6.0 meters from point A to point B within an electric field requires a 5.0-newton force. What is the electric potential difference between points A and B? 60. V 15 V 30. V 2.5 V What does the slope of this graph represent? power force potential difference electric field intensity 118. A 12-volt automobile battery has coulombs of electric charge. The amount of electrical energy stored in the battery is approximately J J J J 119. How much work is required to move a single electron through a potential difference of 100. volts? J J J J

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