Physics Samples E&M Unit 1. Two metal spheres having charges of +4.0 x 10 6 coulomb and +2.0 x 10 5 coulomb, respectively, are brought into contact and then separated. After separation, the charge on each sphere Name Per Date 6. Twenty-four joules of energy expended in moving 2 coulombs of charge a dtance of 3 meters in an electric field. What the potential difference through which the charge moved (A) 8.0 x 10 11 C (C) 2.1 x 10 6 C (A) 48 V (C) 12 V (B) 8.0 x 10 6 C (D) 1.2 x 10 5 C (B) 16 V (D) 4.0 V 2. The charge-to-mass ratio of an electron (A) 9.1 x 10 31 C/kg (C) 5.7 x 10 12 C/kg (B) 1.6 x 10 19 C/kg (D) 1.8 x 10 11 C/kg 3. An electron located 1.0 meter from a +2.0-coulomb charge, as shown in the diagram below. 7. Most metals are good electrical conductors because (A) their molecules are close together (B) they have high melting points (C) they have many intermolecular spaces through which the current can flow (D) they have a large number of free electrons 8. As the value of a variable restor increased, while voltage held constant, the current flow in the restor will (A) decrease (C) remain the same (B) increase 9. A lightning bolt transfers 6.0 coulombs of charge from a cloud to the ground in 2.0 10-3 second. What the average current during th event (A) 1.2 10-2 A (B) 3.0 10 2 A (C) 3.0 10 3 A (D) 1.2 10 4 A The electrostatic force acting on the electron directed toward point 4. Two charges that are 2 meters apart repel each other with a force of 2 x 10 5 Newton. If the dtance between the charges decreased to 1 meter, the force of repulsion will be (A) 1 x 10 5 N (C) 8 x 10 5 N (B) 5 x 10 6 N (D) 4 x 10 5 N 10. A piece of wire has a restance of 8 ohms. A second piece of wire of the same composition, diameter, and temperature, but one-half as long as the first wire, has a restance of (A) 8 Ω (C) 16 Ω (B) 2 Ω (D) 4 Ω 11. The restance of a copper wire measured to be 4 ohms at 20ºC. If the wire heated to 30ºC, the restance of the wire will be (A) zero ohms (C) more than 4 ohms 5. A point charge of +3.0 x 10-7 coulomb placed 2.0 x 10-2 meter from a second point charge of +4.0 x 10-7 coulomb. The magnitude of the electrostatic force between the charges (B) less than 4 ohms (D) 4 ohms (A) 2.7 N (B) 5.4 x 10-2 N (C) 3.0 x 10-10 N (D) 6.0 x 10-12 N s_5xut Page 1
12. The graph below represents the relationship between potential difference and current for four different restors. Which restor has the greatest restance 16. In the circuit shown below, voltmeter V 2 reads 80. volts. 13. If the current in a wire 2.0 amperes and the potential difference across the wire 10. volts, what the restance of the wire (A) 5.0 Ω (C) 12 Ω (B) 8.0 Ω (D) 20 Ω 14. If the potential difference across a 30.-ohm restor 10. volts, what the current through the restor (A) 0.25 A (C) 3.0 A (B) 0.33 A (D) 0.50 A 15. Which voltage would cause a current of 0.5 ampere in a circuit that has a restance of 24 ohms (A) 6.0 V (C) 24 V (B) 12 V (D) 48 V What the reading of voltmeter V 1 (A) 160 V (C) 40. V (B) 80. V (D) 20. V 17. Which circuit segment below has the same total restance as the circuit segment shown in the diagram to the right (A) (B) (C) (D) s_5xut Page 2
18. Ammeters A 1, A 2 and A 3 are placed in a circuit as shown below. 23. The diagram below represents lines of magnetic flux within a region of space. What the reading on ammeter A 3 (A) 1.0 A (C) 3.0 A (B) 2.0 A (D) 5.0 A 19. Two restors are connected in parallel to a 12-volt battery as shown in the diagram. The magnetic field strength greatest at point 24. The diagram below shows the magnetic field that results when a piece of iron placed between unlike magnetic poles. If the current in restance R 3.0 amperes, the rate at which R consumes electrical energy (A) 1.1 x 10 2 W (C) 24 W (B) 36 W (D) 4.0 W 20. An electric motor draws 150 amperes of current while operating at 240 volts. What the power rating of th motor (A) 1.6 W (C) 3.6 10 4 W (B) 3.8 10 2 W (D) 5.4 10 6 W 21. The heating element on an electric stove dsipates 4.0 10 2 watts of power when connected to a 120-volt source. What the electrical restance of th heating element (A).028 Ω (C) 3.3 Ω (B).60 Ω (D) 36 Ω At which point the magnetic field strength greatest 25. Which diagram best illustrates the direction of the magnetic field between the unlike poles of two bar magnets (A) (C) (B) (D) 22. An electric dryer consumes 6.0 x 10 6 joules of energy when operating at 220 volts for 30. minutes (1800 seconds). During operation, the dryer draws a current of approximately (A) 10. A (C) 20. A (B) 15 A (D) 25 A s_5xut Page 3
26. An electron current (e ) moving upward through a straight conductor creates a magnetic field. Which diagram below correctly represents th magnetic field (A) (C) 29. The diagram to the right represents a conductor carrying a current in which the electron flow from left to right. The conductor located in a magnetic field which directed into the page. (B) (D) The direction of the magnetic force on the conductor will be (A) into the page (B) out of the page (C) toward the top of the page (D) toward the bottom of the page 27. Electrons flow in a loop of wire as shown in the diagram. What the direction of the magnetic field at point A Base your answers to questions 30 through 33 on the diagram below. The reading of voltmeter V 1 26 volts, and the reading of ammeter A 1 2 amperes. (A) into the paper (B) out of the paper (C) toward the left (D) toward the right 28. The accompanying diagram shows an electron moving through a magnetic field. 30. What the reading of voltmeter V 2 (A) 52 V (C) 13 V (B) 26 V (D) 8 V If the electron moving out of the page, in which direction will it be deflected by the magnetic field (A) toward the top of the page (B) toward the bottom of the page (C) to the left (D) to the right 31. What the total restance of the circuit (A) ¾ Ω (C) 10 Ω (B) 4/3 Ω (D) 13 Ω 32. The reading of ammeter A 2 (A) 6 A (C) 3 A (B) 2 A (D) 52 A s_5xut Page 4
33. If additional restances are added in series and the applied voltage kept constant, the reading of voltmeter V 3 will (A) decrease (C) remain the same (B) increase Base your answers to questions 39 through 43 on the electric circuit below. The switch in the open position. Base your answers to questions 34 through 38 on the diagram below which represents an electrical circuit. 39. What the reading of ammeter A 1 (A) 1/6 ampere (C) 60. amperes (B) 6.0 amperes (D) 600 amperes 34. The equivalent restance of the circuit (A) 25 Ω (C) 5.0 Ω (B) 6.0 Ω (D) 0.17 Ω 35. The potential difference across R 2 (A) 1.0 V (C) 10. V (B) 2.0 V (D) 12 V 36. The magnitude of the current in ammeter A 1 (A) 120 A (C) 1.2 A (B) 2.0 A (D) 0.83 A 37. Compared to the current in A 1, the current in A 2 (A) less (C) the same (B) greater 38. If another restance were added to the circuit in parallel, the equivalent restance of the circuit (A) decrease (C) remain the same (B) increase 40. What the reading of ammeter A 2 (A) 9.0 amperes (C) 12 amperes (B) 2.0 amperes (D) 18 amperes 41. What power developed in the 10.-ohm restor (A) 600 watts (C) 60. watts (B) 360 watts (D) 6.0 watts 42. Compared to the potential drop across the 10.-ohm restor, the potential drop across the 20.-ohm restor (A) less (C) the same (B) greater 43. Compared to the current passing through ammeter A 1 when the switch open, the current passing through ammeter A 1 when the switch closed will be (A) less (C) the same (B) greater 44. Which segment of copper wire has the highest restance at room temperature (A) 1.0 m length, 1.0 x 10 6 m 2 cross-sectional (B) 2.0 m length, 1.0 x 10 6 m 2 cross-sectional (C) 1.0 m length, 3.0 x 10 6 m 2 cross-sectional (D) 2.0 m length, 3.0 x 10 6 m 2 cross-sectional s_5xut Page 5
45. If both the cross-sectional and the length of a metallic conductor were doubled, the restance of the conductor would be (A) halved (C) unchanged (B) doubled (D) quadrupled 50. the diagram below. 46. The ratio of the potential difference across a metallic conductor to the current in the conductor known as (A) potential drop (C) restance (B) conductivity (D) electromagnetic force 47. A wire carries a current of 6.0 amperes. How much charge passes a point in the wire in 120 seconds (A) 6.0 C (C) 360 C (B) 20. C (D) 720 C The total restance in the circuit (A) 9 Ω (C) 3 Ω (B) 6 Ω (D) less than 3 Ω 48. Base your answer to the following question on the diagram below. What the total restance of the circuit (A) 6.6 Ω (C) 20 Ω (B) 10 Ω (D) 30 Ω 49. When the circuit shown below completed what will be the reading on the ammeter at B (A) less than the reading at A (B) greater than the reading at A (C) the same as the reading at A s_5xut Page 6
Physics Samples E&M Unit Name Per Date 1. D 2. D 3. D 4. C 5. A 6. C 7. D 8. A 9. C 10. D 11. C 12. D 13. A 14. B 15. B 16. A 17. B 18. A 19. B 20. C 21. D 22. B 23. B 24. C 25. B Answer Key 26. D 27. B 28. A 29. D 30. D 31. D 32. B 33. A 34. B 35. D 36. C 37. A 38. A 39. B 40. A 41. B 42. C 43. C 44. B 45. C 46. C 47. D 48. D 49. C 50. D s_5xut