MEC 105 Exam 1 Review Questions From Past Years

MEC 105 Exam 1 Review Questions From Past Years - MEC 105...

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MEC 105 Exam 1 Review Questions From Past Years 1. A photoconductor is a a. Metal b. Insulator c. Semiconductor 2. A photoconductor’s electrical properties go from insulating to conducting when it is exposed to light because a. Light allows extra electrons to move out of the valence band giving the semiconductor a negative charge b. Light allows extra electrons to move into the conduction band giving the semiconductor a negative charge c. Light supplies the energy needed to move electrons from the valence band to the conduction band d. Light lowers the energy of the conduction levels eliminating the energy gap 3. The surface of a photoconductor has been coated with electric charge. This charge will remain in place until you expose the surface to a. An electric field b. A magnetic field c. Both an electric and magnetic field d. Light 4. After running a plastic comb through your hair several times you hold it above a small scrap of paper. The paper jumps off the table and sticks to the comb because the paper becomes a. Magnetic b. Electrically charged c. Conducting d. Electrically polarized 5. If your bicycle tires were made of solid rubber rather than being filled with air, it would be harder to start them spinning because they would have a. a larger angular momentum b. a larger moment of inertia c. a larger torque d. a larger kinetic energy 6. The north pole of a permanent magnet is clinging to the front surface of your steel refrigerator, so the refrigerator clearly has a south pole at its surface. If you flip the permanent magnet over, so that its south pole faces the refrigerator, the refrigerator will a. keep a south pole at its surface and repel the permanent magnet b. keep a south pole at its surface and attract the permanent magnet c. place a north pole at its surface and repel the permanent magnet d. place a north pole at its surface and attract the permanent magnet
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7. You have just pulled your clothes from the dryer and find that a sock is clinging to your jeans with static electricity. You hold the jeans in one hand and the sock in the other and pull the two apart. As jeans and sock move apart, the forces between them become weaker because the a. Electric charge on each garment increases as they move apart b. Electric current passing through each garment diminishes as they move apart c. Electric charge on each garment diminishes as they move apart d. Forces between electric charges become weaker with increasing distance 8. A battery in an operating flashlight a. Does work while transferring positive charge from its negative terminal to its positive terminal b. Does work while transferring positive charge from its positive terminal to its negative terminal c. Has work done on it when positive charge flows from its negative terminal to its positive terminal d. Has work done on it when positive charge flows from its positive terminal to its negative terminal 9. A helicopter is hovering motionless above a disabled boat, while rescue workers use a
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This note was uploaded on 04/08/2008 for the course MEC 105 taught by Professor Kincaid during the Spring '08 term at SUNY Stony Brook.

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MEC 105 Exam 1 Review Questions From Past Years - MEC 105...

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