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NEC > Mike Holt 1 > Flashcards

Mike Holt 1 Flashcards

1
Q

Providing a path to the earth often helps reduce electrostatic charge

A

True

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2
Q

Lighting frequently terminates to a point of elevation and it strikes nonmetallic as well as metallic object with the same frequency

A

True

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3
Q

The termination of the lighting strike is unlikely to ignite combustible materials

A

False

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4
Q

Lighting protection is intended to protect the building structure itself, as well as the electrical equipment on or inside the building structure

A

False

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5
Q

Nonmagnetic metals are ferrous, meaning they do not contain any iron, and cannot be magnetized

A

False

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6
Q

Magnetic lines of force can cross each other and they are called flux lines

A

False

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7
Q

It is not the force of magnetic field through a conductor that produced electricity it is the relative motion of the field the the electrons within the conductor that produces the movement electrons

A

True

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8
Q

People become injured and death may occur with voltage pushes electrons through the human body causing the heart to go into ventricular fibrillation

A

True

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9
Q

The severity of and electric shock is dependent on the current flowing through the body, which is impacted by circuit voltage and contact resistance

A

True

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10
Q

An electrical arc blast can approach ______ Which can vaporize metal parts and produce an explosive deadly pressure wave

A

30,000f

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11
Q

IF a conductor carrying current is next to another conductor carrying current in the opposite direction, The electromagnetic field attempts to push the conductors apart

A

True

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12
Q

A clamp on AC ammeter has a coil that is clamped around the conductor and detects the rising and falling ____ Field
being produced due to the ac flow through the conductor
A. static
B. Current
C. Power
D. Magnetic

A

D. Magnetic

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13
Q 
Ohmmeters measure the \_\_\_\_\_ or opposition to current flow of a circuit or component 
A. Voltage 
B. Current
C. Power
D. Resistance
A

D. Resistance

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14
Q 
The megger is used to measure very high \_\_\_\_\_\_ values such as those found in cable insulation, or motor and transformer windings 
A. Voltage
B. Current 
C. Power
D. Resistance
A

D. Resistance

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15
Q 
The electric motor works on the principle of the attracting and repelling forces of the \_\_\_\_\_ Fields
A. Voltage
B. Current
C. Power
D. Magnetic
A

D. Magnetic

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16
Q 
The\_\_\_\_\_\_\_ of a generator is forced to rotate while it is being subjected to the magnetic field of the stator 
A. Winding 
B. Rotor
C. Stator 
D. B or C
A

B. Rotor

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17
Q

A holding relay is primarily used for workers convenience

A

False

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18
Q

According to the electron current flow theory electrons flow away from the negative terminal of the source through the circuit and load, toward the positive terminal of the source

A

True

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19
Q

According to the conventional current flow theory, electric current travels from positive to negative

A

True

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20
Q

One major advantage of ac over dc is the ease of voltage regulation by the use of a transformer

A

True

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21
Q

The best conductors, in order of their conductivity, Are gold, silver, copper, And aluminum

A

False

Silver, Copper, Gold, Aluminum

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22
Q

In a dc circuit the only opposition to current flow is the physical resistance of the material. The opposition is called reactance and it is measured in ohms

A

False

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23
Q 
The formulas in the power wheel apply to 
A. DC
B. AC with unity power factor 
C. DC or AC circuits 
D. A & B
A

D. A & B

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24
Q

The opposition to current flow results in voltage drop

A

True

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25
Q

Kerchief’s Voltage Law state that in a series circuit the sum of the voltage drops across all of the resistors will equal the applied voltage

A

True

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26
Q 
Kerchief's current law states that in a series circuit the current is \_\_\_\_\_\_ throughout the transformer the conductors and the appliance 
A. Proportional 
B. Distributed 
C. Additive 
D. The same
A

D. The Same

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27
Q

Kerchief’s current law the total current provided by the source to a parallel circuit will equal the sum of the current of all of the branches

A

True

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28
Q

Because of the dangers associated with an open grounded conductor the continuity of the grounded conductor of a multi-wire branch circuit cannot be dependent upon the receptacle

A

True

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29
Q

Electrons leaving a power supply are always trying to return to the same power supply they are not trying to go into the earth

A

True

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30
Q 
The total opposition to current flow in ac circuits is called \_\_\_\_\_\_\_ and is measured in ohms 
A. resistance 
B. reactance 
C. impedance 
D. Skin effect
A

C. impedance

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31
Q

If the primary phase voltage is 480v and the secondary phase voltage is 240v the turns ration is _______

A

2 to 1

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32
Q

In a hotel _______ receptacles shall be readily accessible

A

2

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33
Q

The supply side bonding jumper on the supply side of services shall be sized according to the ________

A

Ungrounded supply conductor size

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34
Q 
Motors shall be located so that adequate \_\_\_\_\_ is provided and so that maintenance such as lubrication of bearings and replacing of brushes can be readily accessible 
A. Space
B. ventilation 
C. Protection 
D. All of these
A

B. Ventalation

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35
Q 
The allowable ampacity of flexible cords and cables is found in \_\_\_\_\_\_\_\_\_
A. Table 310.15
B. Table 400.5(A)(1)
C. Chapter 9 Table 1
D. Table 430.52
A

B. Table 400.5(A)(1)

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36
Q

Except by special permission no conductor larger then _____ AWG shall be installed in a cellular metal floor raceway

A

1/0

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37
Q

The minimum clearance for overhead conductors not exceeding 600v that pass over commercial areas subject to truck traffic is

A

18’

38
Q

At least 1 receptacle shall be installed within 18” of the top of a show window for each ______ section

A

12’

39
Q

The maximum voltage permitted between ungrounded conductors of flat conductors cable systems is _____

A

300v

40
Q

The length of a cord for a dishwashers, trash compactor shall not be more than ______ measured from the back of the appliance

A

4’

41
Q

Where flexible cords are used in ambient temperature other then _______ the temperature correction factors from table 310.15 shall be applied to the ampacity from table 400.5

A

30deg C

42
Q

Metal raceways and metal piping within _____ of a hot tub must be bonded

A

5’

43
Q

A wall mounted laminar weighing not more that _____ can be supported by a 6/32 screws

A

6 ib

44
Q 
Which of the following is not standard size fuse or inverse time circuit breaker 
A. 45A
B. 70A
C. 75A
D. 80A
A

C.75A

45
Q

Underground PVC pipe shall not be closer than ______ unless space limitations prevent otherwise

A

5’

46
Q

For a stationary motor 2hp or less and 300v or less Ac current, the controller can be ac-rated only general-use snap switch where the motor full-load current rating is not more than ________ percent of the rating of the switch

A

80%

47
Q

Mobile home services cannot be less then

A

100a

48
Q

Liquidtight flexible metal conduit must be secured within ____ of the termination

A

1’

49
Q

Portable distribution equipment for carnivals must be located at lease _______ above the ground

A

6”

50
Q

The minimum clearance between an electric space-heating cable and an outlet box used for surface luminaries shall not be less then ______

A

8”

51
Q

PV wires must be grouped at intervals of _______

A

6’

52
Q

Ground wire shall not have to be larger then ______

A

6

53
Q

Cables installed in agriculture buildings shall be secured within ________ of each cabinet, box or fitting

A

8”

54
Q

Isolated ground receptacles are identified with _____

A

Orange Triangle

55
Q

This must be used to provide shore power

A

Circuit breaker or switch both clearly marked

56
Q

An optical fiber cable is a factory assembly of one or more optical fibers having __________ covering that transforms light for control, signaling and communications

A

overall

57
Q

When an elevator room has more then 1 elevator drive they shall be number and ____________

A

identifying the number of drive machinery they control

58
Q

A _________ location may be temporarily subject to dampness and wetness

A

Dry

59
Q

Factory installed internal wiring of listed equipment need not be inspected as the time of installation of equipment ,except to detect alterations or damage

A

True

60
Q

Type mc cable can be unsupported where not more then 2’ of length at terminals where flexibility is necessary
T or F

A

True

61
Q

Compliance with the provisions of the NEC will result in

A

An electrical system essentially free from hazard

62
Q 
Surface non-matalic raceways shall be permitted 
A. in dry locations 
B. where concealed 
C. in hoistways 
D. all of these
A

A. in dry locations

63
Q

A panel board shall be protected by an overcorrect devise within the panel board or at any point on the ______ side of the panel board

A

Supply side

64
Q 
All switchboards, panel boards and motor control centers shall be 
A. located in dedicated spaces 
B. protected from damage 
C. in weatherproof enclosures 
D. A and B
A

D. A and B

65
Q

A devise comprised of ________ or more receptacles shall be calculated at not less then 90 VA per receptacle

A

4

66
Q

A run of RMC shall not contain more than the equivalent of _______ quarter bends between pull points such as conduit bodies and fittings

A

4

67
Q

The branch-circuit, short-circuit protection devise for a 10hp 230v single phase motor shall not exceed _______

Motors can not be sized more than 250% of the motors FLA

A

125a

68
Q

The voltage will lead the current when the inductive reactance exceeds the capacitive reactance

A

True

69
Q

The current will lead the voltage when capacitive reactance exceeds the inductive reactance in the circuit

A

True

70
Q

I = Intensity

A

Current Amps

71
Q

E & Energy V Are (emf)

A

Voltage

72
Q

C=

A

Capacitance

73
Q

L=

A

Inductor

74
Q

R = Resistance

A

ohms

75
Q

P = Power

A

Watts

76
Q

Watts

A

= Power

77
Q

Ohms (resistance)

A

Power Consumed

78
Q

Wasteful circulating ___________in the iron core causes the core to heat up without and useful purpose

A

eddy currents

79
Q

The Energy transfer ability of a transformer is accomplished because the primary electromagnetic lines of force induced a voltage in the secondary windings
T or F

A

True

80
Q

____________ Can be reduced by dividing the core into many flat sections or laminations

A

Eddy Currents

81
Q

The heat from harmonic currents is proposed to the square of the harmonic order

A

True

82
Q

The current flow through the transformer, the iron core is temporarily magnetize. The energy required to realign the core molecules to the changing electromagnetic field is called _________ loss

A

Hysteresis

83
Q

Because of conductor resistance, flux leakage eddy currents and hysteresis losses not all of the input power is transferred to the secondary windings for useful purpose
T or F

A

True

84
Q

In DC circuits, the only opposition to current flow is the physical resistance of the material. This opposition is called reactance and it is measured in ohms

A

False

85
Q 
The formulas in the power wheel apply to \_\_\_\_\_\_
A. DC 
B. AC With unity power factor 
C. DC & AC circuits 
D. A & B
A

DC and AC with unity power factor

86
Q

According to Kirchoff’s Current law, The total current provided by the source to a parallel circuit will equal the sum of the currents of all the beaches

A

True

87
Q 
Because of the earth's high resistance to current flow, it cannot be used for the purpose of clearing a line to case ground fault for \_\_\_\_\_\_\_\_\_ wiring 
A. Utility 
B. Premises
C. A or B
D. None of these
A

Premises

88
Q 
Equipment must have a \_\_\_\_\_\_\_current rating that permits the protection devise to clear a short circuit or ground fault without extensive damage to the components of the circuit
A. Overload
B. Short Circuit 
C. Ground Fault 
D. B or C
A

Short circuit

89
Q 
Arcing is defined as a luminous discharge of electricity across an insulated medium. Electric arcs operates at temperatures between \_\_\_\_\_\_\_and expel small particles of very hot molten materials 
A. 1,000 and 5,000F
B. 2,000 and 10,000F
C. 5,000 and 15,000F
D. 10,000 and 25,000
A

C 5,000 and 15,000

90
Q 
The expanding and collapsing magnetic field within the conductors induces a voltage in the conductors )CEMF) that repels the flowing electrons toward the surface of the conductor. This is called \_\_\_\_\_\_\_
A. eddy currents 
B. induced voltage 
C. impedance
D. Skin Effect
A

Skin effect

91
Q 
Total opposition to current flow in ac circuit is called \_\_\_\_\_
and is measured in ohms 
A. Resistance
B. reactance 
C. impedance 
D. Skin Effect
A

C impedance

NEC (5 decks)

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