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1. Electroplating uses a ___________ generator.
2. The total opposition to the flow of
alternating current is ______.
3. 3 phase currents are generally out of phase
by ____ degrees.
4. ____ is the ratio of output to input.
5. The voltage produce by electromagnetic
induction is controlled by __.
- number of lines of flux cut per second
Which of the following has the highest dielectric strength to electrical breakdown?
The greatest voltage drop in a circuit will
occur when the ____the current flow
through that part of the circuit.
8. ______ results in loss of electrical energy
from the circuit.
Soft iron is most suitable for use in a _______.
As the temperature increases, the resistance
of most conductors also increases
Of the six ways of producing emf, which method
is used the least?
Resistance in the power formula equals ____.
What is the formula to find watt hours?
In a series circuit when the voltage remains
constant and the resistance increases, the current _____.
Other factors remaining the same, the effect on
the current flow in the circuit would cause the current to ___ if the applied voltage
A mil is what part of an inch?
A number 12 wire has a diameter of 80.81
mils. The cma would be ___.
A substance whose molecules consist of the
same kind of atoms is called__.
The electrons in the last orbit of an atom
A length of wire has a resistance of 6 ohms.
The resistance of a wire of the
same material three times as long
and twice the csa will be___ ohms.
The hot resistance of a 100 watt
incandescent bulb is about____times
its cold resistance.
The purpose of load in an electrical circuit
A device for making, breaking, or changing connections in a circuit under
load is a____.
What relationship determines the efficiency
of electrical equipment?
- power output divided by the input
The conductance of a conductor is the ease
in which current flows through
it. It is measured in ____.
In which of the following would a rheostat
most likely not be used?
Nichrome wire having a resistance of 200 ohms
per 1000 feet is to be used for a
heater that requires a total
resistance of 10 ohms. the length
of wire required would be___feet.
A fluorescent light that blink "on" and
"off" repeatly may in
- in damage to the ballast
Electrical appliances are connected in
parallel because it___.
- the operation of appliances independent of each other
IF 18 resistances each 36 ohms are connected
in parallel, the total resistance
would be ___ ohms.
A negatively charged body has ___.
A capacitor stores ___.
Electrical appliances are not connected in
- have different current rating
Permanent magnet use___as the magnetic material.
The armature current drawn by any DC motor
is proportional to the __.
A compnonent having no continuity would have____resistance.
Basically all electric motors operate on
the priciple of repulsion or
Generally the maximum ambient temperature
for operating Class B motors is___.
The change in direction of light passing from
one area to another of different density is called___.
An electrician in the industry would first
check the____ to correct a low
Tinning rubber insulated twisted cable is
- chemical reactions between the copper and the rubber
Inductance in a circuit______.
The AC system is prefered to the DC system because____.
- voltages can be easily change in magnitude
The breakdown voltage of an insulation
depends upon____ value of AC
As the power factor of the circuit is increased___.
- power is decreased
For the same rating, the size of a 3 phase motor will be____ a single phase motor.
Carbon brushes are used on a commutator because___.
DC series motor are used in applications where___is required.
The voltage per turn of the primary of a transformer is ____the voltage
per turn of the secondary.
A 480/208/120v 3 phase transformer is
connected delta-wye. The
secondary line voltage of the
transformer is___in the secondary.
- than the phase voltage
_____equipment or materials to which has been attached a label, symbol,or other identifying
mark of an organization that is
acceptable to the
authority having jurisdiction and concerned with product evaluation that maintains
periodic inspection of
equipment or materials and indicates
with appropriate standards or
What is the reason the Code requires each separate phase conductor to be located in the same raceway?
A three phase delta-wye connected
transformer, 480v primary, 208/120v
secondary, the secondary line current
- to the secondary phase current
Circuit breakers shall be marked with a voltage rating no less than the nominal system
voltage that is indicative of
their capability to interupt.
I. fault currents between
II. fault currents from
the phase to ground
III. fault currents
between the neutral and ground
The most common type of base used on
standard incandescent light
bulbs of 300 watts or less
A___of a switch is that part of a switch which
is used for the making or breaking
of a connection and which is
electrically insulated from other
contact making or breaking parts.
The point of attachment of service drop conductors to a building or other
structure shall in no casse be
less than ______ feet.
_____of the following is the true statement.
I. wiring above a nonfire
rated ceiling shall not be
supported by the ceiling support wires
II. wiring above a fire
rated ceiling shall not be
supported by the ceiling support wires
III. cables and raceways
shall not be permitted to be
supported by ceiling grids
IV. the ceiling support
wires shall be permitted to
support branch circuit wiring in accordance if with the ceiling manufacturer's
An insulated ground receptacle shall be identified by_____.
- orange triangle located on the face of the receptacle
The speed of the DC motor can be controlled by____.
- the field current while the armature
- current is held constant
If a three-phase, delta-wye transformer bank having a 480v primary and a
208/120v secondary, is considred
to be 100% efficient,and to have
resistive-typeloads,the maximum kva of the load will be___.
I. equal to the kva of the
secondary of the transformer
II. equal to the primary
kva of the transformer
III. considerably less than the kva of the
Surrounded by a case,housing,fence or walls that prevent persons from accidentally
contacting energized parts
_______means that equipments is not readily accesible to persons unless special
means for access are used.
________locations are those that are
hazardous because of the presence
of easily ignitable fibers or
A transformer would most likely have an efficiency of ____percent.
Where lighting outlets are installed in
interior stairways, there shall be
a wall switch at each floor level
to control the lighting outlet where
the difference between floor level is____steps or more
The installation of wiring and equipment for
fire alarm systems including all
circuits contolled and powered
by the fire alarm system is covered
A conducting material that is____charged
will have an excess of
When three single phase transformers are connected in such a way that the
line current is equal to the phase
current this transformer
_______losses in an iron core transformer
occur when materials are used that
retain a large part of their
magnetization after the magnetizing force
is removed. These materials are said to have a high permanence
The difference between a neutral and a
grounded circuit conductor is
- a neutral carries unbalanced
A piece of electrical equipment that is
designed to operate at alternate
intervals of (1) load and no load;
or (2) load and rest; or (3) load, no
load, and rest is called____duty.
Insulated conductors of #____or smaller,
intended for use as grounded
conductors of circuits shall have
an outer identification of white or natural gray color.
_____covers and plates shall be permitted with nonmetallic boxes.
I. nonmetallic II. metal
A light fixture to be installed in a wet location shall be____.
I. installed so that
water will not accumalate in
II. installed so that
water will not enter the
III. marked suitable for
The general requirements for communication circuits such as
wiring for fire alarm and burglar alarms is covered in article____of the NEC.
Thermal protection is required by the NEC for_____.
I. fluorescent lighting
fixture ballast installed indoors
lighting fixture ballast installed
incandescent fixtures installed
All conductors of the same circuit and, where used, the grounded conductor and all
equipment grounding conductors
shall be contained within the
I. cable II. raceway
When a circuit breaker is in the OPEN position_______.
I. you have a short in
the ungrounded conductor
II. you have a short in
the grounded conductor
An electrical outlet constructed so that
moisture will not enter the
enclosure is classified as
You have an adjustable trip coil rated at 5
amps on a 200-amp switch. If you
want the switch to trip at 120
amps, the trip coil should be set
After cutting a conduit, to remove the
rough edges on both ends, the
conduit ends should
One should use an insulated basket grip to attach a pull line to the conductors because a
bare steel grip should not be
used because it will___.
- the conduit during the pull
The instrument used to indicate phase
relation between current and
voltage is the________.
Reactance will cause the current in a circuit
to vary only when___.
Fixtures supported by the framing members of suspended ceiling systems shall be
securely fastened to the
ceiling framing member by
mechanical means.This would include all but which of the following?
With two conductors installed in a conduit,
the conduit can be filled to______%
of its cross section.
In a residence, no point along the floor line
in any wall space may be more than
_____feet from an outlet.
Which of the following electrode must be supplemented by an
- water pipe
plaster, drywall or plasterboard surfaces
that are broken or incomplete
shall be repaired so there will be
no gaps or open spaces greater
than_____inch at the edge of the fitting box.
When making electrical connections a torque screw driver or wrench is required because
I. many terminations and
equipment are marked with a
II. control circuit
devices with screw-type pressure
terminals used with #14 or smaller copper conductors shall be torqued to a
minimum of 7 lb-in. unless
identified for a different torque
III. listed or labeled
equipment shall be installed and
used in accordance with any instructions included in the listing or labeling
The SPST switch can control______.
In the OFF position, a good switch will
The tool that is used to align vitrified
tile conduit in multiple ducts
is a _____.
A transformer is associated with_____current.
Relay contact are made of
A device that serves to govern, in some predetermined manner, the electric
power delivered to the apparatus to
which it is connected is
conductors drawn from a copper-clad aluminum
rod with the copper metallurgically
bonded to an aluminum core.
The copper forms a minimum of
____percent of the csa.
Operation of equipment in excess of normal, full-load rating, or of a conductor in
excess of rated ampacity which,
when it persists for a sufficient
length of time, would cause damage or
dangerous overheating is called______.