Chapter 2: Magnetism Practice Test
 1. High-voltage wires are best for long distance electrical wires, but are dangerous for household use. A transformer may be used to change the voltage to an appropriate amount. What is the working principle behind a transformer?
 a. Spinning a coil of wire near a permanent magnet induces a current. b. Electrical energy is converted to mechanical energy, then back to electrical energy. c. An electrical current in one wire is used to induce a current in another wire. d. All of the above.
 2. The magnetic field of Earth protects us from high-energy, charged particles from the sun. What is the fate of the charged particles that encounter Earth's magnetic field?
 a. Particles interfere with radio reception and electrical power lines. b. Particles are trapped in a region over the equator called the Van Allen Belts. c. An electrical current in one wire is used to induce a current in another wire. d. All of the above.
 3. If two bar magnets, with labeled north and south poles, are brought close together and allowed to interact, what might you observe?
 a. Two north poles attract, two south poles repel. b. Two north poles repel, two south poles attract. c. Like poles repel, different poles attract. d. Like poles attract, different poles repel.
 4. It is possible to construct a magnet using a coil of wire and a battery. What can you do with the wire to increase the strength of the magnetic field of your electromagnet?
 a. increase the voltage of the battery b. increase the number of coils in the wire c. wrap the coil of wire around an iron bar d. All of the above.
 5. Suppose you take two bar magnets and you slowly move the north poles of the magnets closer to one another. What do you observe?
 a. The poles repel and the force between the poles increases. b. The poles repel and the force between the poles decreases. c. The poles attract and the force between the poles decreases. d. The poles attract and the force between the poles increases.
 6. How are magnetic domains related to magnetism?
 a. The magnetic fields of domains of magnetic substances are aligned. b. The magnetic fields of the domains of non-magnetic substances are not aligned. c. Induced magnetism causes the magnetic fields of domains to align themselves. d. All of the above.
 7. How does Magnetic Resonance Imaging work?
 a. A changing magnetic field is used to perform surgery without cutting. b. An electromagnetic wave is used to detect magnetic fields in the body. c. A large magnet helps the body repair arthritic joints. d. All of the above.
 8. Where are the magnetic field lines closest together in the magnetic field surrounding a bar magnet?
 a. between the poles b. It is impossible to say. c. at the poles d. away from the poles
 9. A thousand years ago, the Chinese used needles of lodestone to navigate their ships. What kind of magnet were these mariners using?
 a. electromagnets b. temporary magnets c. permanent magnets d. induced magnets
 10. How do loudspeakers work?
 a. A constantly changing electric signal moves through a coil of wire. b. An electromagnet is used to vibrate a permanent magnet. c. A coil of wire is used to make an electromagnet. d. All of the above.
 11. What is the working principle behind an electric generator?
 a. Spinning a coil of wire near a permanent magnet induces a current. b. Electrical energy is converted to mechanical energy. c. A coil of wire is used to make an electromagnet. d. All of the above.
 12. Suppose a charged particle from the sun is traveling through Earth's magnetic field. What effect does the magnetic field have on this moving charge?
 a. The magnetic field has no effect on the direction of the traveling particle. b. The magnetic field exerts a force on the particle in the direction of the magnetic field. c. A coil of wire is used to make an electromagnet. d. All of the above.
 13. If a bar magnet is brought near an iron nail, the nail becomes magnetic and is attracted to the bar magnet. What is the term used to describe the magnetism of the iron nail?
 a. electromagnetism b. temporary magnetism c. induced magnetism d. magnetic domination
 14. Suppose you find a bar of magnetite and you hang it from a string. The bar swings freely in the air, but the two ends of the bar tend to point north and south. What are the two ends of the bar called?
 a. magnetic fields b. a dial compass c. magnetic poles d. leading poles
 15. What happens when a conductor experiences changing magnetic field?
 a. An electric current is induced in the conductor. b. The conductor causes a magnetic field reversal. c. magnetic poles d. All of the above.