31 Jan 20. Suppose that an electric

Question 1
1. Combining which of the following substances with germanium will cause the germanium to emit free electrons?

A. Indium

B. Gallium

C. Aluminum

D. Bismuth

Question 2

2. Which of the following is true in regard to a charged atom?

A. When an atom gains an electron, it becomes a cation, which is positively charged.

B. The magnitude of the negative charge is equal to the magnitude of the positive charge.

C. The number of protons and the number of electrons within the same atom are unequal.

D. When an atom loses an electron, it becomes an anion, which is negatively charged.

Question 3

3. When an electric current flows through a long conductor, each free electron moves

A. from one end of the conductor to the other end.

B. back and forth between the ends of the conductor.

C. with a speed of 300,000,000 m/s.

D. through a relatively short distance.

Question 4

4. Which of the following would experience induced magnetism most easily?

A. Copper

B. Aluminum

C. Air

D. Permalloy

Question 5

5. Suppose that you’re facing a straight current-carrying conductor, and the current is flowing toward you. The lines of magnetic force at any point in the magnetic field will act in

A. a clockwise direction.

B. the direction opposite to the current.

C. a counterclockwise direction.

D. the same direction as the current.

Question 6

6. A transformer has a primary voltage of 115 V and a secondary voltage of 24 V. If the number of turns in the primary is 345, how many turns are in the secondary?

A. 1,653

B. 8

C. 690

D. 72

Question 7

7. Which of the following is true about semi-conductors:

A. Gold and silver are important semiconductors

B. A material is classified as a semiconductor if its resistance to the flow of electric current is too low to permit it to be called a conductor

C. Neither free electrons nor holes are considered charge carriers in a semi-conductor

D. Exposing a crystal of a semiconductor to heat or light starts displacing valence electrons which then move throughout the crystal

Question 8

8. A battery consists of five dry cells connected in series. If the voltage developed by each cell is 1.5 V, the total voltage developed by the battery is

A. 1.5 V.

B. 7.5 V.

C. 0.3 V.

D. 5.0 V.

Question 9

9. Which of the following is an example of electrical energy being converted to chemical energy?

A. A storage battery is charged using an electric current.

B. The wheels on a machine begin to turn and move a conveyer belt.

C. An electric furnace begins to emit heat to warm a house.

D. A loudspeaker, which is plugged in to the wall, begins to project sound.

Question 10

10. Which of the following does not serve as a way to neutralize the charge in a body?

A. Adding free electrons to a positively charged body

B. Adding more protons to a positively charged body until the number of protons matches the number of electrons

C. Bringing the charged body into contact with another body having an equal but opposite charge

D. Allowing free electrons to escape from a negatively charged body

Question 11

11. If a bar of copper is brought near a magnet, the copper bar will be

A. attracted by the magnet.

B. made into an induced magnet.

C. repelled by the magnet.

D. unaffected by the magnet.

Question 12

12. Which of the following devices is associated with the reception of radio signals?

A. Oscillator

B. Microphone

C. Transmitting antenna

D. Demodulator

Question 13

13. A current of 9 A flows through an electric device with a resistance of 43 ?. What must be the applied voltage in this particular circuit?

A. 4.8 A

B. 4.8 V

C. 387 V

D. 387 A

Question 14

14. Which of the following is an accurate description of the relationship demonstrated in Ohm’s Law?

A. The electric potential (volts) divided by the current (amperes) equals the resistance (ohms).

B. The electric potential (volts) multiplied by the resistance (ohms) equals the current (amperes).

C. The electric potential (amperes) divided by the resistance (ohms) equals the current (volts).

D. The resistance (ohms) divided by the current (amperes) equals the electric potential (volts).

Question 15

15. The relationship between a cathode and an anode involves

A. electrons.

B. diodes.

C. protons.

D. neutrons.

Question 16

16. Which of the following usually occurs with a short circuit?

A. All parts of the circuit will begin to carry lower amounts of current than normal.

B. The material within a fuse may begin to melt when the current ceases to exist.

C. All parts of the circuit will begin to carry higher amounts of current than normal.

D. Most of the current will flow through one part of the circuit.

Question 17

17. When an electron is displaced in a semiconductor, the hole that’s left behind is

A. considered an impurity in the crystal.

B. attracted to the anode of the voltage source.

C. incapable of carrying a charge.

D. attracted to the negative terminal of the voltage source.

Question 18

18. When all parts of a circuit are composed of conducting materials, the circuit is said to be

A. closed.

B. open.

C. parallel.

D. shorted.

Question 19

19. An electric heating element is connected to a 110 V circuit and a current of 3.2 A is flowing through the element. How much energy is used up during a period of 5 hours by the element?

A. 352 Wh

B. 2,580 Wh

C. 1,760 Wh

D. 550 Wh

Question 20

20. Suppose that an electric charge is produced on one part of a body. If the charge spreads through the entire body, the body is most likely made of

A. porcelain.

B. metal.

C. plastic.

D. oil.