Deck 8: Electricity and Magnetism

Question 1

The unit for current is the

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

Answer 1

A

Question 2

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.

Answer 2

A

Question 3

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.

Answer 3

A

Question 4

In a conductor,what moves?

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

Question 5

The unit of resistance is called a(n)

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

Question 6

Electric charge is measured in units of

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

Question 7

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 8

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 9

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 10

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

Question 11

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 12

The abbreviation of the unit of resistance is

A) $\Psi$
B) $\Delta$
C) $\Sigma$
D) $\Omega$
E) $\Pi$

Question 13

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 14

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 15

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 16

Ohm's law gives the relationship between

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

Question 17

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 18

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 19

One ampere × one second is a unit of

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

Question 20

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 21

The source of magnetism is

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

Question 22

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 23

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 24

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 25

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 26

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 27

Voltage is defined as the ______________ per unit ______________.

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

Question 28

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 29

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

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

Question 30

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 31

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 32

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 33

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 34

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

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

Question 35

The electrical power dissipated in an appliance depends on

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

Question 36

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 37

Which of the following would be the least conductive?

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

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

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 40

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 41

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 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

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 44

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 45

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

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

Question 46

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 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) toward the south pole.
D) toward the north pole.

Question 48

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 49

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 50

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 51

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 52

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

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

Question 53

An ac voltage can be increased or decreased easily using a

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

Question 54

A motor converts

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

Question 55

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 56

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

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

Question 57

A ferromagnetic material is magnetized by the alignment of

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

Question 58

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 59

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 60

A ferromagnetic material loses this property above the ______________ temperature.

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

Question 61

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

Question 62

Another name for electric potential difference is ______________.

Question 63

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

Question 64

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

Question 65

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

Question 66

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

Question 67

Two oppositely charged particles ______________ one another.

Question 68

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

Question 69

Power may be expressed as _____________ times resistance.

Question 70

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 71

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 72

The expression V = IR is called ______________.

Question 73

The unit of electric current is the ______________.

Question 74

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

Question 75

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

Question 76

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

Question 77

According to the law of charges,unlike charges ______________.

Question 78

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

Question 79

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 80

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.