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1.44 kW

A lamp operated at 120V has a resistance of 10 Ω. What is the wattage of the lamp: 1.44 kW 1 kW

0.2

Induction motor during no load condition will have a power factor in the range: 0.7 0.2 0.5 0.9

Tin

Which material is used in the fuse: Iron Copper Lead Tin

1440 Ohms

A 240V, 40 W tungsten lamp has a working resistance of: 1250 Ohms 1380 Ohms 1440 Ohms 1400 Ohms

b. Only in Article 240

Definitions within Article 240 apply to what section(s) of the NEC? Throughout the NEC Only in Article 240 Chapters 1, 2, 3, and 4 Chapters 5, 6, and 7

True

A non sinusoidal voltage and current waveforms are generated when a non linear load is connected to supply system: True False

1 Ω

The equivalent resistance of three resistances each of 3Ω connected in parallel will be: 9 Ω 1 Ω 4.5 Ω 1.5 Ω

B. B phase shall

11. A general Code rule is, as viewed from the front of a switchboard or panelboard the _____ be the phase having the higher voltage to ground on 3-phase, 4-wire delta-connected systems. A. A phase shall B. B phase shall C. C phase shall D. Any phase is permitted to

d. 22.5 feet

4. Determine the minimum clearance for overhead service conductors crossing over a residential pool. This measurement is the distance from the water surface to the 120 volts to ground overhead service conductors. 10 feet 14.5 feet 18 feet 22.5 feet

b.2

5. Determine the minimum number of receptacles required to be installed to serve countertop appliances in a kitchen island that has a rectangular countertop measuring 3 feet wide by 8 feet long. 1 2 3 There is no requirement to install receptacles for island countertops

Both AC and DC circuits

A Wattmeter can be used to measure power in: DC circuits only AC circuits only None of the above circuits Both AC and DC circuits

5.25 ohms

A resistance of 5ohms is connected in series with a parallel of four resistances each of 1 ohm. What will be the equivalent resistance of the circuit 4.75 ohms 5.25 ohms

B. 6 feet

According to the Code, flexible metal conduit (FMC) enclosing circuit conductors is not approved for use as a type of an equipment grounding conductor in lengths exceeding _____. A. 4 feet B. 6 feet C. 8 feet D. 10 feet

b. 538 square feet

All wind turbines shall be required to have a readily accessible manual shutdown button or switch, unless they have a swept area less than ______. 500 square feet 538 square feet 560 square feet 583 square feet

a. Equipment grounding conductor

Capacitor cases shall be connected to the ______. Equipment grounding conductor Grounding electrode conductor Grounded conductor Ungrounded conductor

D. 70 pounds

Ceiling-suspended (paddle) fans weighing more than _____ shall be supported independently of the outlet box. A. 35 pounds B. 50 pounds C. 30 pounds D. 70 pounds

c. 6 feet 7 inches

Circuit breakers and switches containing fuses shall be located so that they may be operated from a readily accessible place. They shall be installed such that the center of the grip of the operating handle of the switch or circuit breaker, when in its highest position, is not more than ______ above the floor or working platform. 6 feet 6 feet 6 inches 6 feet 7 inches 7 feet

b. 24 inches

Determine the length of a straight pull box where the conduit entering the box is a 3-inch EMT containing four 4/0 THHN conductors. 16 inches 24 inches 30 inches 32 inches

c. 225 A

Determine the maximum standard ampere rating of an overcurrent protection device for a 1,000 VA control transformer with a single-phase 480-volt primary and single-phase 120-volt secondary. The control transformer will have primary protection only. 80 A 200 A 225 A 350 A

d. 18 feet

Determine the minimum vertical clearance above finished grade required for overhead service conductors over a commercial driveway subject to truck traffic. 10 feet 12 feet 15 feet 18 feet

5

Determine the number of wall space receptacles required to be installed in the room shown in the figure below. graphic for question 3 5 6 7

b. Indoors, underground, or in metal enclosures

Distribution cutouts rated over 1,000 volts nominal shall not be used ______. Outdoors, aboveground, or in non-metallic enclosures Indoors, underground, or in metal enclosures At less than their maximum rated voltage Where the fused cutouts are interlocked with a switch to prevent opening the cutouts under load

c. Other than one- or two- family dwellings

Each disconnecting means shall be legibly marked to indicate its purpose unless located and arranged so the purpose is evident. In ______, the marking shall include the identification of the circuit source that supplies the disconnecting means. One-family dwellings Two-family dwellings Other than one- or two- family dwellings Industrial settings

Fleming's Right hand rule

Electrical Generator works on the principle of: Fleming's left hand rule Maxwell's law Fleming's Right hand rule Amperes rule

c. Exit signs

For health care facilities, which of the following branches are not permitted to be arranged for delayed automatic connection to the alternate power source? Central suction system serving medical and surgical functions Compressed air systems serving medical and surgical functions Exit signs Smoke control and stair pressurization systems

C. 4/0 AWG

For one-family dwellings supplied by a single-phase, 120/240-volt system, and having a 200-ampere rated inverse time circuit breaker for the main disconnecting means, what minimum size THWN aluminum conductors are permitted for use as ungrounded service-entrance conductors? Given: No adjustment or correction factors are required. A. 2/0 AWG B. 3/0 AWG C. 4/0 AWG D. 250 kcmil

Both resistance and inductance

Generally motor load can be represented by: Combination of Resistance, Inductance and Capacitance Both resistance and inductance Inductance alone Resistance alone

A. four

If a 1¾ in. deep, single-gang, Type FS device box houses a duplex receptacle, how many insulated size 12 AWG conductors are permitted to be enclosed in the FS box? A. four B. five C. six D. eight

False

Impact of Electro-static charge on a surface of a body cannot be reduced by connecting the surface to the ground True False

720 watts

In a 60Hz a.c circuit, its voltage is 120V and current is 12A, the current lags the voltage by 60 deg. Find the power in watts: 850 watts 720 watts

True

In a circuit supplying power to capacitive loads, voltage waveform will lag behind the current waveform: False True

D. 50 feet, 70 feet

In compliance with the rules established by the NEC®, all 120-volt, single-phase, 15- and 20-ampere branch circuits supplying outlet or devices in specific areas or rooms of a dwelling unit shall be provided with arc-fault circuit-interrupter protection. Where Type NM cable is used as the wiring method for "home runs" in the dwelling, the maximum length of the cable from the overcurrent device to the first outlet shall not exceed _____ for size 14 AWG NM cable and _____ for size 12 AWG NM cable. A. 50 feet, 75 feet B. 40 feet, 60 feet C. 40 feet, 50 feet D. 50 feet, 70 feet

A. in a professional and skillful manner

In reference to the mechanical execution of electrical work, the 2023 edition of the NEC states, electrical equipment shall be installed _____. A. in a professional and skillful manner B. with neatness and completeness C. skillfully, with good workmanship D. according to the rules established by the local authority having jurisdiction

Part III

In what part of Article 100 can you find definitions applicable to hazardous (classified) locations? Part I Part II Part III Part IV

Resistance

Megger is used to measure which of the following: Ampere-hour Resistance Voltage Power factor

False

Single phase induction motor is a self starting motor: False True

False

Single phase induction motor is a self starting motor: true or false

B. in a readily accessible location outdoors

The Code mandates a clearly labeled emergency disconnect is to be provided at each service for one- and two-family dwelling units. The emergency disconnect is permitted to be installed _____. A. at an accessible location in the garage B. in a readily accessible location outdoors C. anywhere outdoors D. in a readily accessible location within 6 feet of the garage entry

b. 1½ hours

The batteries of individual unit equipment for legally required standby illumination shall be of suitable rating and capacity to supply and maintain at least 60% of the initial emergency illumination for a period of at least ______ without the voltage falling below 87½% of normal voltage. 1 hour 1½ hours 2 hours 2½ hours

B. 24 inches

The required 15- or 20-ampere receptacle outlet for a peninsular countertop or work surface in the kitchen of a dwelling must be located not further than _____from the outer edge of the peninsular countertop. A. 12 inches B. 24 inches C. 18 inches D. 20 inches

Both Insulating material and coolant

Transformer oil used in Electrical Transformer acts as: Insulating material Coolant It depends on the application of tranformer Both Insulating material and coolant

b. 80 amperes

Two dual element (time-delay) type RK5 fuses are used as the motor branch-circuit short-circuit and ground-fault protection for a 7½ horsepower, single-phase 208-volt motor. What is the maximum allowable current rating of these fuses? 70 amperes 80 amperes 110 amperes 125 amperes

77.7 %

What is the efficiency if a 10-hp motor draws 40 amps at 240V? 77.7 % 96.5% 97.1% 86.1 %

b. 5 feet

What is the maximum spacing between supports for trade size 2-inch rigid polyvinyl chloride conduit (PVC)? 3 feet 5 feet 6 feet 7 feet

B. 3/0 AWG

What is the required size 75°C copper service-entrance conductors for a 200-ampere, 120/240-volt, single-phase commercial service where elevated ambient temperature is not a concern? A. 4/0 AWG B. 3/0 AWG C. 2/0 AWG D. 1/0 AWG

C. weatherproof

When single-phase, 125-volt, 15- or 20-ampere receptacles are housed in a device box located outdoors in a wet location, the receptacles shall have an enclosure that is listed as _____ whether or not the attachment plug cap is inserted. A. watertight B. extra-duty C. weatherproof D. raintight

A. 14 AWG

Where Type NM cable is used as the wiring method for "home runs" for power and lighting branch circuits in a dwelling, the minimum size copper required is _____. A. 14 AWG B. 12 AWG C. 10 AWG D. either A or B

D. 469 amperes

Where a 112½ kVA transformer having a single-phase, 120/240-volt secondary is installed at a multifamily dwelling unit, the full-load current rating, in amperes, of the secondary is ____. A. 938 amperes B. 625 amperes C. 313 amperes D. 469 amperes

a. Grounding electrode

Where a portable generator is the source of an optional standby system and is used as a non-separately derived system, the equipment grounding conductor shall be bonded to the system ______. Grounding electrode Grounded conductor Main bonding jumper Any of the above

A. GFCI protection

Where a single 125-volt, single-phase, 20-ampere receptacle outlet located in an attached garage of a dwelling unit is provided for a central vacuum assembly, the receptacle outlet is required to have _____. A. GFCI protection B. AFCI protection C. LCDI protection D. a nonmetallic faceplate

A. 115 percent

Where an inverse-time circuit breaker is used as a disconnecting means for an air-conditioning unit, the ampere rating of the circuit breaker shall be not less than _____ of the A/C nameplate rated-load current or branch-circuit selection, whichever is greater. A. 115 percent B. 125 percent C. 150 percent D. 175 percent

C. 310.15(C)(1)

Where four (4) or more current-carrying conductors are installed in a common raceway, the ampacity of each current-carrying conductor must be determined by applying the percentage values as given in Table _____ of the Code. A. 310.15(B)(2)(a) B. 310.15(B)(1)(1) C. 310.15(C)(1) D. 310.15(B)(3)

d. Enclosed within the same raceway or other enclosure as required in 300.20

Where installed in a metal raceway or enclosure, all conductors of all feeders using a common neutral conductor shall be ______. Enclosed within a listed electromagnetic interference (EMI) cable shielding jacket Wrapped with a wire mesh tape where conductors are routed near metal parts of any enclosure Both a and b Enclosed within the same raceway or other enclosure as required in 300.20

D. Both I and II

Where insulated power and lighting conductors are installed in raceways, an ampacity adjustment must be applied where _____. I. there are more than three (3) current-current carrying conductors in the same raceway II. an ambient temperature other than 86°F is encountered A. I only B. II only C. either I or II D. both I and II

D. 83 percent

Where one- and two family dwellings are supplied with a single-phase, 120/240-volt electrical system from the local utility company and the service demand load is not more than 400 amperes, for sizing the ungrounded (phase) service-entrance conductors, the conductors shall be permitted to have an ampacity of not less than _____ of the values shown in Table 310.16 A. 70 percent B. 75 percent C. 80 percent D. 83 percent

c. Hoistway pit lighting shall be connected to the load side of a ground-fault circuit interrupter.

Which of the following is NOT true for elevator hoistway pit lighting and receptacles? A separate branch circuit shall supply the hoistway pit lighting and receptacles. The lighting switch shall be located so as to be readily accessible from the pit access door. Hoistway pit lighting shall be connected to the load side of a ground-fault circuit interrupter. At least one 125-volt, single-phase, 15- or 20-ampere duplex receptacle shall be provided in the hoistway pit.

Electrical Transformer

Which of the following machine has higher efficiency of the following Electrical Transformer Synchronous machine Induction motor DC Motor

electrical current

Which of the following quantity is same in a series electrical circuit: Electrical Current Electrical Resistance Electrical Power Electrical Voltage

D. All of the above.

Which of the following single-phase receptacle outlets in a dwelling are required to have ground-fault protection for personnel? A. A 250-volt, 30-ampere clothes dryer receptacle in the utility room. B. A 125-volt, 20-ampere receptacle in the kitchen for a built-in waste disposer. C. 125-volt, 15- or 20-ampere receptacles located above a kitchen countertop. D. All of the above.

Eddy Currents

__ are wasteful circulation currents observed in iron cores which results in loss of energy Both Hysteresis and Eddy Currents Core Currents Eddy Currents Hysteresis Currents


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