214

Power is measured in ___. I. watts II. volt-amperes Select one: a. I only b. II only c. either I or II d. neither I nor II

c

An AC circuit that has only resistive loads connected to it will result in current and voltage being in phase with each other. Select one: a. True b. False

a

Apparent power is measured in ___. Select one: a. volt-amps b. watts c. volt-amps reactive

a

Circuit impedance (Z) consists of both the resistive and reactive components of a load. Select one: a. True b. False

a

Correction of power factor is generally required due to the presence of ___. Select one: a. induction motors b. incandescent lighting

a

For an AC circuit, current and voltage are in phase with each other when ___. Select one: a. XL + XC = 0 b. R = 0

a

For temporary installations, the NEC® requires that receptacles be ___. Select one: a. of the grounding type b. protected at not less than 30 amperes c. made of thermoplastic d. all of these

a

The apparent power used by an induction motor circuit is ___ the true power delivered by the motor. Select one: a. greater than b. the same as c. less than

a

Total opposition to current flow in an AC circuit is referred to as ___. Select one: a. impedance b. reactance c. resistance d. none of these

a

True Power is the power used in a circuit by purely ___ loads or components of a circuit. Select one: a. resistive b. inductive c. capacitive d. all of these

a

When temporary installations operate at over 600 volts, access shall be limited to ___. Select one: a. authorized and qualified personnel b. authorized personnel c. full-time employees d. electricians only e. any of these

a

Which of these power factors is the best? Select one: a. 100% b. 75% c. 50% d. 25%

a

Apparent power can be ___ true power. I. more than II. equal to III. less than Select one: a. I or II or III b. I or II only c. II only d. I only e. II or III only

b

For temporary installations, Type NM and Type NMC cables shall be permitted to be used in any dwelling, building, or structure, up to a maximum height of ___ feet. Select one: a. 20 b. there is no height limitation. c. 30 d. 40

b

The impedance of a series circuit is ___ ohms. The circuit has a resistance of 25 ohms, an inductive reactance of 14 ohms and a capacitive reactance of 10 ohms. Select one: a. 29 b. 25.3 c. 27 d. 7 e. 49

b

The phase angle of a circuit is 28 degrees. The power factor is ___%. Select one: a. 46.9 b. 88.3 c. 28 d. 72

b

___ power is the power required to supply both resistive and reactive components of a load or loads. Select one: a. Reactive b. Apparent c. True

b

A series circuit has both inductive and capacitive loads. The loads supply equal reactance to circuit current. Which of the following statements is true? I. The current through each load is 180 degrees out of phase with the other. II. The inductive and capacitive currents add together with a net current of zero. Select one: a. I only b. II only c. both I & II d. neither I nor II

c

Capacitor banks are rated in ___. Select one: a. KW b. KVA c. KVAR

c

For temporary wiring over ___ volts, nominal, suitable fencing, barriers, or other effective means shall be provided to limit access only to authorized and qualified personnel. Select one: a. 250 b. 300 c. 600 d. 1000

c

In a series circuit where inductive reactance is less than capacitive reactance, resulting in a negative phase angle, current will ___ voltage. Select one: a. be in phase with b. lag c. lead

c

In temporary installations, receptacles shall not be connected to the same ungrounded conductor of multiwire circuits that supply ___. Select one: a. GFCI receptacles b. emergency lighting c. temporary lighting d. motors

c

Specific to temporary installations, how does the NEC® address protecting flexible cords and cables that run on sharp corners? Select one: a. Not addressed within the Article. b. No special precautions due to the temporary nature of the installation. c. Sharp corners should be avoided. d. Use heavy duty cords.

c

The total current in a series circuit is ___ Amps. The circuit is supplied from a 2-pole breaker in a 120/208-V 3-ph panel. The circuit has a resistance of 25 ohms, an inductive reactance of 14 ohms and a capacitive reactance of 10 ohms. Select one: a. 25.32 b. 14.26 c. 8.2 d. 10.22 e. 9.48

c

___ power is power consumed by a resistor, dissipated as heat, and not returned to the generation source. Select one: a. Reactive b. Apparent c. True

c

Apparent power is measured in ___. Select one: a. hertz b. ohms c. watts d. volt-amps e. volt-amps reactive

d

Impedance is measured in ___. Select one: a. volts b. amps c. Zs d. ohms e. none of these

d

In an AC circuit the total opposition to current flow is referred to as ___. Select one: a. capacitive reactance (XC) b. resistance (R) c. inductive reactance (XL) d. impedance (Z)

d

Temporary electric power and lighting installations shall be permitted during the period of construction, remodeling, maintenance, ___, or demolition of buildings, structures, equipment, or similar activities. Select one: a. framing b. cleaning c. renovation d. repair

d

If the power factor of a load is 0.73, the phase angle, , is ___ degrees. Select one: a. 46.9 b. 95.6 c. 73 d. 29.2 e. 43.1

e

Poor power factor could occur as the result of the presence of ___. I. electric resistance heating equipment II. 120-volt incandescent lighting III. refrigeration equipment using induction motors Select one: a. I & II only b. I & III only c. I, II & III d. I only e. III only

e

The power factor for a load is ___% where true power = 11 kW & apparent power = 12 kVA. Select one: a. 16.3 b. 10.9 c. 73.7 d. 47.8 e. 91.7

e

Which of the following is (are) measured in ohms? I. inductive reactance (XL) II. impedance (Z) III. capacitive reactance (XC) .IV. resistance (R) Select one: a. II & III only b. IV only c. I & III only d. II & IV only e. I, II, III & IV

e