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Unit 9

Physics

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Unit 9.07 – Electricity and Magnetism: 10 Multiple Choice Questions 1. In which type of circuit does adding resistors cause the overall resistance to go up? Select one: a. In neither type of circuit. b. In series circuits only. c. In parallel circuits only. d. In both series and parallel circuits. 2. A glass rod is rubbed on a piece of silk. The glass rod and piece of silk are then hung from string and brought near each other. What will be observed? Select one: a. They will attract each other because they have opposite charges. b. They will attract each other because they have the same charge. c. They will repel each other because they have the same charge. d. They will repel each other because they have opposite charges. 3. A positive current is allowed to go through a wire in the direction shown. Which way with the North Pole of the compass, which is below the wire, point once the current is flowing? Select one: a. Left b. Right. c. Down d. Up 4. What would happen if I tried to move an aluminum plate through a very strong magnetic field? Select one: a. Plate will interact with the field causing it to be easier to move. b. Plate will interact with the field causing a drag-like force. c. There will be no interaction between the field and the plate. 5. A compass is near a magnet, the North end of the compass is pointing at the magnet. If the magnet is flipped over (so the N and S ends are reversed), what will happen to the compass? Select one: a. The compass would turn 90 degrees. b. The compass will continue to point the same way. c. The compass will point the opposite way. 6. What happens to the amount of charge flow (current), as the resistance is increased. Select one: a. It remains the same. b. It increases. c. It decreases. 7. Two bulbs are hooked up to the same potential difference. Bulb A has twice the current through it compared to bulb B. How do the power output of the two compare? Select one: a. Bulb A has twice the power. b. Bulb A will have four times less power. c. Bulb A has four times the power. d. Bulb A has half the power. 8. Which type of circuit consists of multiple paths for charge to follow? Select one: a. Open b. Closed c. Parallel d. Series 9. Which of the following shows a complete circuit that would be capable of lighting the bulb? Choose all that are correct. Select one or more: a. b. c. d. 10. Choose all of the following materials that will interact with a magnet in a noticeable way. (You can select more than one answer.) Select one or more: a. A plastic spoon. b. Stainless steel objects such as a dinner fork. c. A copper penny. d. An iron paperclip. Unit 9.07 – Electricity and Magnetism: 20 Questions (12 Multiple Choice Questions, 8 Fill-in-the-Blank Questions). 1. In which type of circuit does the current through each resistor add up to the overall current in the circuit? Select one: a. In neither type of circuit. b. In parallel only. c. In series only. d. In series and parallel. 2. Two charged metal spheres experience an attractive force of 1 N when they are 2 m apart from each other. How far away from each other will they need to be to experience a force of 4 N? Select one: a. 0.5 m b. 1m c. 4m d. 8m 3. A compass is set under a wire that is running in a North-South direction. What will happen to the compass as the current through the wire is slowly increased in the direction indicated. The compass is currently pointing in the direction of the Earth's magnetic field. Select one: a. The compass will gradually rotate clockwise to a maximum of 90 degrees. b. The compass will gradually rotate counter-clockwise to a maximum of 90 degrees. c. The compass will continually rotate clockwise to a maximum of 180 degrees. d. The compass will continually rotate counter-clockwise to a maximum of 180 degrees. 4. Two unknown objects are brought near each other and they attract. No matter which way they are brought up next to each other, they still attract. What are the two unknown objects? Select one: a. Both are magnets. b. One is a magnet and one is a magnetic material. c. Both are magnetic materials. 5. Two bulbs are hooked up to the same potential. Bulb A has twice the resistance of bulb B. How will the power output of the bulbs compare? Select one: a. Bulb A will have twice the power. b. Bulb A will have four times more power. c. Bulb A will have half the power. d. Bulb A will have four times less power. 6. In which type of circuit is the current always the same through every component? Select one: a. Open b. Closed. c. Parallel d. Series 7. What MUST be present in order for charge to flow. Choose all that apply. Select one or more: a. A conducting path from high to low potential. b. Wires c. A charge receptacle. d. Light bulbs. e. A battery. f. A source of potential difference. 8. What must be true of the electrons in magnetic materials (ferromagnetic)? Select one: a. It must have many paired electrons. b. It must have less electrons than protons. c. It must have many unpaired electrons. d. It must have more electrons that protons. 9. In which of the following technologies is a conductor moved within a magnetic field to produce a current? Select one: a. Generator. b. Electric Motor. c. Transformer. 10. What is the slope of a graph of current vs. voltage? Select one: a. Resistance. b. Charge c. Power 11. What is the voltage across a 10 ohm resistor that has 2 amps of current going through it? Answer: ________________________________ 12. What is the current through a 5 ohm resistor that has 10 volts across it? Answer: ________________________________ 13. What is the resistance of a light bulb that has 0.1 amps through it when a potential difference of 3 volts is applied? Answer: ___________________________________ 14. What is the overall resistance of three 10 ohm resistors in series? Answer: __________________________________ 15. What is the overall resistance of two 100 ohm resistors in parallel? Answer: ____________________________________ 16. Find the effective resistance of the the circuit depicted here. Answer: _____________________________ 17. How much power is used by a bulb that has 5 ohms of resistance and a current of 0.2 amps? Answer: ______________________________ 18. Two charged spheres have an attractive force between them of 2.0 N. What will the force between them be if the charge on each sphere is doubled and the distance between them is also doubled? Answer: ________________________________ 19. Two light bulbs one 40 watt and one 60 watt when hooked up in parallel in 120 volt circuit. Which will be brighter when hooked up and series with each other and why? Select one: a. The 40 watt bulb, it has less resistance so a higher current. b. The 60 watt bulb, it has higher resistance so a larger voltage drop. c. The 60 watt bulb, it has less resistance so a higher current. d. The 40 watt bulb, it has higher resistance so a larger voltage drop. 20. The conventional current is going through the coil of wire shown here in a clockwise direction. Which way does the magnetic field of this coil of wire point? Select one: a. To the right. b. To the left. c. Away from you. d. Towards you