Deck 8: Electricity and Magnetism

Question 1

An object that is negatively charged will

A) repel a rubber rod stroked with fur.
B) repel a glass rod stroked with silk.
C) be polarized.
D) none of these

Answer 1

A

Question 2

Electric charge is measured in units of

A) coulombs.
B) watts.
C) volts.
D) newtons.

Answer 2

A

Question 3

The unit for current is the

A) ampere.
B) ohm.
C) coulomb.
D) volt.

Answer 3

A

Question 4

A system of 12 electrons and 18 protons has a net charge of

A) 9.6 × 10^-19 C.
B) -9.6 × 10^-19 C.
C) 17.6 × 10^-19 C.
D) 6.0 × 10^-19 C.
E) -17.6 × 10^-19 C.

Question 5

A system of an electron and a neutron has a net charge of

A) +1.6 × 10^-19 C.
B) -1.6 × 10^-19 C.
C) 3.2 × 10^-19 C.
D) zero.

Question 6

One ampere × one second is a unit of

A) power.
B) current.
C) voltage.
D) electric charge.
E) resistance.

Question 7

The abbreviation of the unit of resistance is

A)
B)
C)
D)
E)

Question 8

A system of an electron, a proton, and a neutron has a net charge of

A) +1.6 × 10^-19 C.
B) -1.6 × 10^-19 C.
C) 3.2 × 10^-19 C.
D) zero.

Question 9

A system of 8 electrons, 18 protons, and 4 neutrons has a net charge of

A) 16.0 × 10^-19 C.
B) -16.0 × 10^-19 C.
C) 22.4 × 10^-19 C.
D) 10.0 × 10^-19 C.
E) -22.4 × 10^-19 C.

Question 10

An object that is positively charged will

A) repel a rubber rod stroked with fur.
B) repel a glass rod stroked with silk.
C) be polarized.
D) none of these

Question 11

An object that is positively charged will

A) attract a rubber rod stroked with fur.
B) attract a glass rod stroked with silk.
C) be polarized.
D) none of these

Question 12

A system of a proton and an electron has a net charge of

A) +1.6 × 10^-19 C.
B) -1.6 × 10^-19 C.
C) 3.2 × 10^-19 C.
D) zero.

Question 13

An object that is negatively charged will

A) attract a rubber rod stroked with fur.
B) attract a glass rod stroked with silk.
C) be polarized.
D) none of these

Question 14

The unit of resistance is called a(n)

A) volt.
B) ampere.
C) coulomb.
D) ohm.
E) watt.

Question 15

The mathematical form of Coulomb's law is similar to that of

A) the second law of thermodynamics.
B) the second law of motion.
C) Kepler's second law.
D) the law of gravitation.

Question 16

A system of 11 protons and 15 neutrons has a net charge of

A) 17.6 × 10^-19 C.
B) -17.6 × 10^-19 C.
C) 41.6 × 10^-19 C.
D) 11.0 × 10^-19 C.
E) -41.6 × 10^-19 C.

Question 17

In a conductor, what moves?

A) Electrons
B) Neutrons
C) Quarks
D) Protons

Question 18

Ohm's law gives the relationship between

A) current and voltage.
B) work and current.
C) current and charge.
D) force and current.

Question 19

A system of 18 electrons and 11 neutrons has a net charge of

A) -28.8 × 10^-19 C.
B) 28.8 × 10^-19 C.
C) -11.2 × 10^-19 C.
D) -18.0 × 10^-19 C.
E) 11.2 × 10^-19 C.

Question 20

A system of a proton and a neutron has a net charge of

A) +1.6 × 10^-19 C.
B) -1.6 × 10^-19 C.
C) 3.2 × 10^-19 C.
D) zero.

Question 21

A component in an automobile 12-V electrical system has a resistance of 90 Ω. How much current is in the component when in operation?

A) 100 A
B) 0.13 A
C) 7.5 A
D) 1100 A

Question 22

If work is done on an electric charge, a ______________ is present.

A) resistance
B) current
C) voltage
D) transformer
E) bigger charge

Question 23

For an ohmic conductor, current is

A) directly proportional to voltage.
B) directly proportional to resistance.
C) independent of resistance.
D) independent of voltage.

Question 24

For electrical safety,

A) electrical shocks caused by 1 A of current are of no concern.
B) fuses or circuit breakers are wired in series in circuits.
C) fuses larger than the rated value can be placed in a circuit.
D) fuses and circuit breakers are wired in parallel in circuits.

Question 25

The electric company charges a home on the basis of consumption of

A) resistance.
B) energy.
C) current.
D) voltage.
E) power.

Question 26

Three resistors, 90 Ω, 40 Ω, and 60 Ω, are wired in series and connected to a 120-V battery. What is the equivalent resistance for this circuit?

A) 190 Ω
B) 19 Ω
C) 0.053 Ω
D) 216000 Ω

Question 27

In a battery circuit with different resistors in parallel,

A) the total resistance is larger than the value of the largest resistor.
B) the current is the same through each resistor.
C) the total resistance is larger than the value of the smallest resistor.
D) the voltage is the same across each resistor.

Question 28

The source of magnetism is

A) polarization.
B) magnetic monopoles.
C) electrons.
D) protons.

Question 29

The electrical power dissipated in an appliance depends on

A) voltage.
B) current.
C) resistance.
D) all of these.

Question 30

If the voltage across a resistor is tripled, the current will

A) remain the same.
B) be cut to one-third.
C) be cut by one-third.
D) be tripled.
E) be multiplied by nine.

Question 31

Three resistors, 30 Ω, 20 Ω, and 60 Ω, are wired in series and connected to a 120-V battery. What is the equivalent resistance for this circuit?

A) 110 Ω
B) 10 Ω
C) 0.1 Ω
D) 36000 Ω

Question 32

Magnetism results from

A) the movement of magnetic particles.
B) the movement of electric charge.
C) Earth's magnetic field.
D) the movement of magnetic charge.

Question 33

Three resistors, 20 Ω, 10 Ω, and 80 Ω, are wired in series and connected to a 120-V battery. How much current flows in this circuit?

A) 1.1 Α
B) 20 Α
C) 740 Α
D) 0.0075 Α

Question 34

The electrical power dissipated by a resistance R is

A) inversely proportional to I.
B) directly proportional to I².
C) directly proportional to I.
D) none of these.

Question 35

If the voltage across a resistor is doubled, the current will

A) remain the same.
B) be cut to one-fourth.
C) be cut in half.
D) be doubled.
E) be quadrupled.

Question 36

For an ohmic conductor, current is

A) inversely proportional to voltage.
B) inversely proportional to resistance.
C) independent of resistance.
D) independent of voltage.

Question 37

Voltage is defined as the ______________ per unit ______________.

A) charge; current
B) work; current
C) charge; work
D) work; charge

Question 38

Three resistors, 80 Ω, 10 Ω, and 70 Ω, are wired in parallel and connected to a 120-V battery. How much current flows in this circuit?

A) 0.75 Α
B) 15 Α
C) 950 Α
D) 0.0021 Α

Question 39

A component in an automobile 12-V electrical system has a resistance of 20 Ω. How much energy is dissipated by the component each second?

A) 0.14 J
B) 7.2 J
C) 1.7 J
D) 0.6 J

Question 40

Which of the following would be the least conductive?

A) Copper
B) Salt water
C) Glass
D) Mercury

Question 41

The direction of the magnetic field of a bar magnet is

A) in the direction opposite to that in which a compass would point.
B) in any direction.
C) toward the south pole.
D) toward the north pole.

Question 42

Consider a wire at rest in a magnetic field as shown in the following figure. What will happen to the wire?

A) A current will flow in the wire.
B) The wire will be pushed perpendicular to the plane of the magnetic field.
C) The wire will be pushed toward the north pole.
D) Nothing will happen.

Question 43

A motor converts

A) electricity into magnetism.
B) electrical energy into mechanical energy.
C) mechanical energy into electrical energy.
D) force into power.

Question 44

Consider a wire in a magnetic field, as shown in the following figure, with a current flowing upward through it. What will happen to the wire?

A) The wire will be forced toward the north pole.
B) The wire will be forced perpendicular to the plane of the magnetic field, into the page.
C) The wire will be forced perpendicular to the plane of the magnetic field, out of the page.
D) The current will cease flowing.
E) The wire will be forced toward the south pole.

Question 45

Consider a wire in a magnetic field, as shown in the following figure, with a current flowing through it. What will happen to the wire?

A) The wire will be forced toward the north pole.
B) The wire will be forced perpendicular to the plane of the magnetic field.
C) The current will cease flowing.
D) Nothing will happen.

Question 46

A ferromagnetic material loses this property above the ______________ temperature.

A) domain
B) Faraday
C) Curie
D) Coulomb

Question 47

The direction of the magnetic field of a bar magnet is

A) in the direction opposite to that in which a compass would point.
B) in any direction.
C) away from the south pole.
D) away from the north pole.

Question 48

A ferromagnetic material is magnetized by the alignment of

A) domains.
B) atoms.
C) single magnetic dipoles.
D) poles.

Question 49

Consider a wire in a magnetic field, as shown in the following figure, with a current flowing downward through it. What will happen to the wire?

A) The wire will be forced toward the north pole.
B) The wire will be forced perpendicular to the plane of the magnetic field, into the page.
C) The wire will be forced perpendicular to the plane of the magnetic field, out of the page.
D) The current will cease flowing.
E) The wire will be forced toward the south pole.

Question 50

A(n) ______________ is an elementary particle with no charge.

A) electron
B) neutron
C) proton
D) atom

Question 51

A transformer with 600 turns on the primary coil is used to decrease the voltage from 3000 V to 120 V for home use. How many turns should be in the secondary coil?

A) 600 turns
B) 15000 turns
C) 24 turns
D) 3720 turns

Question 52

A(n) ______________ is an elementary particle with a charge of -1.6 × 10^-19 C.

A) electron
B) neutron
C) proton
D) atom

Question 53

Earth's magnetic field

A) results from a huge bar magnet within the planet.
B) is believed to arise from currents within the planet's core.
C) is always parallel to the planet's surface.
D) is always in the same direction.

Question 54

An insulator has a negative electric charge of 2.4 × 10 -17 C. How many electrons were added or removed?

A) 150 electrons removed
B) 67 electrons removed
C) 150 electrons added
D) 67 electrons added

Question 55

The direction of the magnetic field of a bar magnet is

A) in the direction a compass would point.
B) in any direction.
C) away from the south pole.
D) toward the north pole.

Question 56

The angle between true north and the direction in which a compass needle points is called the angle of

A) attack.
B) inclination.
C) declination.
D) dip.

Question 57

An ac voltage can be increased or decreased easily using a

A) battery.
B) transformer.
C) fuse.
D) motor.
E) generator.

Question 58

A(n) ______________ is an elementary particle with a charge of +1.6 × 10^-19 C.

A) electron
B) neutron
C) proton
D) atom

Question 59

A generator is a device that converts

A) heat energy into mechanical energy.
B) chemical energy into electrical energy.
C) mechanical energy into electrical energy.
D) electrical energy into mechanical energy.

Question 60

An insulator has a positive electric charge of 8 × 10 -17 C. How many electrons were added or removed?

A) 500 electrons removed
B) 20 electrons removed
C) 500 electrons added
D) 20 electrons added

Question 61

A(n) ______________ is an elementary particle with a charge of +1.6 × 10^-19 coulomb.

Question 62

According to the law of charges, unlike charges ______________.

Question 63

The expression V = IR is called ______________.

Question 64

Voltage has the units of ______________, which is called a volt.

Question 65

If a negatively charged object is brought near a suspended, positively charged object, the suspended object will be ______________.

Question 66

The expression that mathematically describes the force between two static electric charges is called ______________.

Question 67

If a positively charged object is brought near a suspended, positively charged object, the suspended object will be

A) repelled.
B) charged more.
C) discharged.
D) attracted.

Question 68

An object may be electrically neutral, but regions may be charged by ______________.

Question 69

In a(n) ______________, electrons do not move freely.

Question 70

Power may be expressed as _____________ times resistance.

Question 71

The maximum current would flow in a set of resistors connected in ______________.

Question 72

The rate of flow of electric charge is measured in units called ______________.

Question 73

If a negatively charged object is brought near a suspended, negatively charged object, the suspended object will be

A) repelled.
B) charged more.
C) discharged.
D) attracted.

Question 74

Another name for electric potential difference is ______________.

Question 75

Two oppositely charged particles ______________ one another.

Question 76

The unit of electric current is the ______________.

Question 77

If a positively charged object is brought near a suspended, negatively charged object, the suspended object will be

A) repelled.
B) charged more.
C) discharged.
D) attracted.

Question 78

To prevent a home electric circuit from overheating because of too much current, a(n) ______________ is used.

Question 79

If a negatively charged object is brought near a suspended, positively charged object, the suspended object will be

A) repelled.
B) charged more.
C) discharged.
D) attracted.

Question 80

The resistances are added in a(n) ______________ circuit.