Name:    Electricity & Magnetism Unit Test (Chapter 32-37)

Multiple Choice
Identify the choice that best completes the statement or answers the question.

1

Potential difference acts like an “electric pressure” that produces ______________.
 a. resistance c. an electrical current b. voltage d. electrical pressure

2

A transistor circuit is used as an amplifier. When a signal is applied to the input of the transistor, the output signal is
 a. zero amplitude. c. a smaller amplitude. b. an equal amplitude. d. a larger amplitude.

3

(2 Points) What would the voltmeter read in the circuit diagram below?

 a. 24 V c. 2 V b. 12 V d. 6 V

4

In circuits of metal wires, _____________ are the flowing charged particles.
 a. electrons c. protons b. neutrons d. protons or electrons

5

(2 Points) A 6 V battery delivers a 0.5 A current to an electric motor that is conncected across its terminals.  What is the power consumed by the motor?
 a. 0.5 W c. 12 W b. 3 W d. 6 W

6

A metal bar magnet has a magnetic field in theregion of space around it. The magnetic field is due to
 a. a hidden voltage source in the metal. c. magnetic monopoles embedded in the metal b. the motion of charged particles in the metal. d. an electric current that runs along the length of the magnet.

7

Any path along which electrons can flow is called a __________.
 a. potentiometer c. wire b. electrical pathway d. electrical circuit

8

When a 4-V battery is connected to a resistor, 2 A of current flows in the resistor. What is the resistor's value?
 a. 3 ohms b. 8 ohms c. 4 ohms d. 2 ohms e. more than 8 ohms

9

(2 Points) What is the current flowing in the circuit below?

 a. 1.0 A b. 12 A c. 6.0  A d. 36 A

10

A charged object has electric potential energy by virtue of its ___________ in an electric field
 a. charge c. direction b. location d. none of the above

11

(2 Points) What is the current through the battery?
 a. 6 A c. 2 A b. 288 A d. 8 A

12

(2 Points) What is the voltage across each of the 4 ohm resistors?
 a. 36 V b. 0.17 V c. 6 V d. 12 V

13

Electrical current is measured in _____________.
 a. coulomb's / second c. amperes b. watts d. both a and c

14

A difference between electrical forces and gravitational forces is that electrical forces include
 a. separation distance. b. the inverse square law. c. repulsive interactions. d. infinite range. e. none of the above

15

A ________________ is a device is used in electrical circuits to store charge
 a. resistor c. insulator b. transistor d. capacitor

16

The units for electrical potential are ____________.
 a. volts c. joules/coulomb b. amperes d. both a and c

17

A coil with a current is shown above. In the center of the coil, a magnetic field points
 a. downward. c. to the right. b. upward. d. to the left.

18

The SI unit of "charge" is the ______________.
 a. coulomb c. joule b. watt d. ampere

19

Materials through which charges do not move easily.  (e.g. glass, dry wood, most plastics, cloth, and dry air) are called _____________.
 a. circuits c. insulators b. conductors d. ionic compounds

20

(2 Points) What is the current flowing in the battery below?

 a. 4 A b. 2 A c. 36  A d. 3 A

21

The electric field extends radially away from the __________.
 a. protons c. ions b. neutrons d. electrons

22

The nucleus of an atom is composed of__________________.
 a. protons c. neutrons b. electrons d. both protons and neutrons

23

(2 Points) When plugged into a 120-V wall outlet, how much current is used by a lightbulb rated at 100 W?
 a. 12,000 A b. 100 A c. 120 A d. 0.8 A e. none of the above

24

(2 Points) What is the total resistance in the circuit below?

 a. 10 W c. 16 W b. 4 W d. 2 W

25

Protons and electrons
 a. do not interact. b. repel each other. c. attract each other.

26

The  rate at which energy is       transferred is called ____________.
 a. energy c. power b. work d. current

27

(2 Points) In this circuit, what is the current through the 2.0-ohm resistor?

 a. 0.2 A c. 5.0 A b. 2.0 A d. 20 A

28

(2 Points) Two charges, qA, and qB, are separated by a distance, d, and exert a force, F, on each other.  Analyze Coulomb’s law and identify what new force will exist if qA is tripled ?
 a. force will be cut in by a third c. force will be increased by factor of ½ b. force will be tripled d. no effect on force

29

What affect would tripling the voltage in a circuit have on the current.
 a. increase it by a factor of 6 c. decrease it by a third b. no effect d. triple it

30

Touching a charged body to earth to eliminate excess charge is called __________.
 a. static equilibrium c. grounding b. l d. charging

31

(2 Points) A car battery causes a current of 1.0 A through a lamp while 48 V is across it.  What is the power used by the lamp?
 a. 0.80 watts c. 12.0 watts b. 48 watts d. 24 watts

32

(2 Points) What is the voltage across the 10 ohm resistor?

 a. 0.4 V b. 10 V c. 2.4 V d. 24 V

33

Normally atoms have a ______ net charge
 a. negative c. positive b. zero d. either positive or negative

34

A 100-watt light bulb is connected to a 120-V outlet. How much current is in the light bulb?
 a. 0.42 A b. 1.67 A c. 6 A d. 0.83 A e. more than 6 A

35

Which of the following statements is not true concerning electrical force?
 a. like charges repel c. unlike charges attract b. Force is directly proportional to distance d. electrical force is a vector quantity

36

An electric field has
 a. direction. b. magnitude. c. Both A and B

37

(2 Points)The current through a 5-ohm resistor connected to a 130-V power supply is
 a. 26 A. b. 10 A. c. 130 A. d. 1A. e. none of the above

38

A charged atom is called a ____________.
 a. compound c. isotope b. radioactive d. ion

39

The second right-hand-rule is use to determine ____________________.
 a. the direction of force c. the  direction of the magnetic field b. the direction of current flow d. the polarity of an electromagnet

40

Which of the following will effect the resistance of a wire?
 a. the length of the wire c. the diameter of the wire b. temperature d. all of the above

41

(2 Points) The current flowing through 3 identical 2 ohm resistors is 5 amperes.  What is the potential difference?
 a. 60  V b. 10 V c. 2.5 V d. 30 V

42

(2 Points) What is the voltage across each of the lightbulbs in the circuit diagram below?
 a. 24 V c. 16 V b. 8 V d. 12 V

43

(2 Points) A motor with an operating resistance of 5 W is connected to a voltage source.  The current in the circuit is 2.0 A.  What is the voltage of the source?
 a. 2.5 volts c. 10.0 volts b. 0.20 volts d. 1.0 volts

44

Every atom composed of (+) positively charged nucleus surrounded by (-) negatively charged ______________.
 a. electrons c. ions b. protons d. neutrons

45

Materials that allow charges to move about easily (e.g. metals, plasma (ionized gas), graphite) are called _____________.
 a. ionic compounds c. conductors b. insulators d. circuits