Energy, electricity and magnetism page 3 Name: 1. Date: The diagram below shows an object made from a battery, a nail, and some wire. What will happen if you touch a metal paperclip to the nail? 2. A. The wires will melt. B. The battery will spark. C. The nail will give you a shock. D. The paperclip will stick to the nail. Which of the following electromagnets would have the greatest magnetic eld? A. B. C. D. page 1 3. A balloon has a negative charge. A glass rod has a positive charge. What will happen when the glass rod is brought near the balloon? 4. A. The balloon will be attracted to the rod. B. The balloon will be repelled by the rod. C. The balloon will remain in place. D. The balloon will spin in circles. Look at the diagram of the bar magnets below. What will happen to the force between the two magnets if they are pulled farther apart? A. The force would be weaker. B. C. The force would stay unchanged. D. The force would reverse the poles. page 2 The force would be stronger. Energy, electricity and magnetism page 3 5. The diagram below shows current ow through a wire. Which of the following represents the magnetic eld resulting from the current? 6. A. B. C. D. A balloon is rubbed with a piece of cloth. As a result, the balloon has a negative charge. What has happened? A. Electrons have moved from the inside to the outside of the balloon. B. Positive charges have traveled from the balloon to the cloth. C. Electrons have moved from the balloon to the cloth. D. Electrons have traveled from the cloth to the balloon. page 3 Energy, electricity and magnetism page 3 7. Electricity in one form or another appears all around you, from lightning in the sky to bonds between atoms that hold molecules together. Each diagram shows two pith balls (foam balls coated with aluminum) hanging from strings. A pith ball can be given a positive (+) or a negative ( ) electrical charge. Which of the following diagrams shows a correct way in which the charged balls will be attracted to or repelled by each other? A. 8. B. C. D. The diagram below shows pieces of scrap iron being picked up by a metal disk hanging from a crane. The pieces of scrap iron are attracted to the metal disk. The metal disk is most likely functioning as which of the following? A. a battery B. an engine C. page 4 an insulator D. an electromagnet Energy, electricity and magnetism page 3 9. 10. Which of the following describes an object that must have a net negative charge? A. It contains more molecules than atoms. B. It contains more electrons than protons. C. It is carrying an electric current. D. It is made of metal. The diagram below shows copper wire wrapped around a cardboard tube, which is then attached to a galvanometer. A galvanometer detects and measures small amounts of electric current. Which of the following would cause the galvanometer needle to move? A. wrapping additional wire around the tube B. uncoiling the wire wrapped around the tube C. moving a magnet back and forth inside the tube D. moving an aluminum block up and down inside the tube page 5 Energy, electricity and magnetism page 3 11. A copper sphere, a glass sphere, a plastic sphere, and a rubber sphere are placed on individual insulating stands. A student touches each sphere with an electrically charged object. The sphere made of which material will distribute the electric charge fastest over its entire surface area? A. 12. copper B. glass C. plastic D. rubber A student places one magnet above another magnet as shown below. Why does the top magnet appear to oat above the bottom magnet? A. The magnets are made of di erent material. B. The like poles of the magnets repel each other. C. The opposite poles of the magnets repel each other. D. The magnets have a di erent gravitational attraction. page 6 Energy, electricity and magnetism page 3 13. A doorbell contains a simple electromagnet. Which change would most likely increase the strength of an electromagnet? A. 14. longer wires B. fewer wire coils C. an aluminum core D. a larger power source When a plastic rod is rubbed with fur, the plastic rod becomes negatively charged. Which statement explains the charge transfer between the plastic rod and the fur? A. Protons are transferred from the plastic rod to the fur. B. Protons are transferred from the fur to the plastic rod. C. Electrons are transferred from the plastic rod to the fur. D. Electrons are transferred from the fur to the plastic rod. 15. Look at the diagram of the circuit below. Which statement best describes what will happen if Bulb 2 burns out? A. Bulb 1 will also burn out. B. C. Bulb 1 will stay lit and become brighter. D. Bulb 1 will stay lit but will become less bright. page 7 Bulb 1 will ash on and o . Energy, electricity and magnetism page 3 16. Each picture shows a light bulb connected to a battery. Which bulb will light? A. 17. B. C. D. The diagram below shows an electrical circuit. This circuit is a series circuit because A. it has two light bulbs. B. C. it uses a single battery. D. the current is divided between the light bulbs. page 8 the same current ows through both light bulbs. Energy, electricity and magnetism page 3 18. 19. Assuming that the light bulbs and batteries are the same, which of these circuits would allow light bulb A to shine the brightest? A. B. C. D. Which of the following statements best compares direct current (DC) and alternating current (AC)? A. AC ows in only one direction, and DC ows in both directions. B. DC ows in only one direction, and AC ows in both directions. C. AC comes directly from a power plant, and DC comes from a magnetic eld. D. DC can maintain a constant voltage over time, and AC loses voltage over time. 20. Solar photovoltaic energy is useful as a portable power source for items such as calculators. In a solar photovoltaic system, sunlight is directly converted into which of the following? A. heat B. electricity C. page 9 nuclear energy D. chemical energy Energy, electricity and magnetism page 3 21. Which of the following statements describes an electric generator? A. A magnet is rotated through a coil of wire to produce an electric current. B. Electric potential in a rotating coil of wire creates a permanent magnet. C. An electrical current causes a coil of wire to rotate in a magnetic eld. D. Forces from a permanent magnet allow a coil of wire to rotate. 22. Some objects conduct electricity. Which object is the best conductor of electricity? A. 23. a metal fork B. a wood spoon C. a plastic comb D. a rubber eraser Most electrical wires are covered with plastic or rubber. The wires are covered with plastic or rubber because those materials A. are conductors of electricity B. C. are not conductors of electricity D. make the electricity move quickly page 10 make complete electric circuits Energy, electricity and magnetism page 3 24. The following image shows Device X, found in a power grid system. What is the role of this device within the electrical grid system? A. It is a generator that produces the current needed inside the home. B. It is a distributor that diverts power from the distribution line to the home. C. It is a transformer that reduces the voltage between the power line and the home. D. It is a regulator that limits the amount of electric power in the wire to the home. page 11 Energy, electricity and magnetism page 3 25. A student builds an electromagnet using a variable power source and 40 turns of wire. The electromagnet is used to pick up metal paper clips. The student changes the voltage and counts the number of paper clips that are picked up. Which table could be the data the student collected? A. Voltage (V) 3 6 9 12 C. Voltage (V) 3 Number of Paper Clips Voltage (V) 24 3 8 9 12 6 Number of Paper Clips D. 12 18 Voltage (V) 20 9 12 10 6 12 page 12 27 24 3 20 Number of Paper Clips 6 10 6 9 B. 21 Number of Paper Clips 9 18 27 36 Energy, electricity and magnetism page 3 26. The diagrams below show a model airplane. Which energy transformation occurs in a rubber band powered model airplane when it is own? A. Thermal energy stored in the rubber band is transformed into chemical energy used by the propeller. B. Kinetic energy stored in the rubber band is transformed into thermal energy used by the propeller. C. Chemical energy stored in the rubber band is transformed into potential energy used by the propeller. D. Potential energy stored in the rubber band is transformed into mechanical energy used by the propeller. 27. Which of the following converts electrical energy into motion? A. light switch B. electric stove C. page 13 light bulb D. electric fan Energy, electricity and magnetism page 3 28. Windmills are used to convert wind energy into a more useful form. In most cases, there are three steps in this process. The energy is in a di erent form at each step. Which of the following owcharts shows the most likely order of the energy changes? A. wind energy ! mechanical energy ! solar energy B. wind energy ! thermal energy ! mechanical energy C. wind energy ! solar energy ! electrical energy D. wind energy ! mechanical energy ! electrical energy 29. The picture below shows a lit bulb. Which sentence explains what happens to the electric energy as the light shines? A. The electric energy gets used up. B. The electric energy changes into light and heat energy and is destroyed. C. The electric energy is created again after it produces light and heat energy. D. The electric energy changes into light and heat energy and is not destroyed. 30. Which device produces mechanical energy? A. a battery B. an electric motor C. page 14 a lightbulb D. a solar cooker Energy, electricity and magnetism page 3 Problem-Attic format version 4.4.220 c 2011–2014 EducAide Software _ Licensed for use by Eva O'Hare Terms of Use at www.problem-attic.com Energy, electricity and magnetism page 3 07/24/2015 1. Answer: D 21. Answer: A 2. Answer: D 22. Answer: A 3. Answer: A 23. Answer: C 4. Answer: A 24. Answer: C 5. Answer: B 25. Answer: D 26. Answer: D D 6. Answer: 7. Answer: B 27. Answer: 8. Answer: D 28. Answer: 9. Answer: B 29. Answer: D 10. Answer: C 30. Answer: B 11. Answer: A 12. Answer: B 13. Answer: D 14. Answer: D 15. Answer: C 16. Answer: D 17. Answer: B 18. Answer: C 19. Answer: B 20. Answer: B