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WorksheetsMASTER CLOSEBOOK EXAM #8
Total questions: 49
Worksheet time: 25mins
A high spot temperature in a controlled in an electrical connection is caused by a (an) ______.
increase in the flow of current through the connection
decrease in the voltage drop across the connection
increase in the voltage drop across the connection
decrease in the effective resistance of the connection
A hickey is ________.
a tool used to bend small sizes of rigid conduit
a part of conduit
not used in electrical trade
used only by a plumber
The lubricant used for a motor sleeve bearing would be _____.
vaseline
grease
oil
graphite
The resistance of the circuit may vary due to_______.
a loose connection
change in voltage
change in current
induction
The service connecting means for each set of service-entrance conductor shall consist of not more than ____ switches.
6
8
10
12
A light bulb usually contains _____.
air
neon
H2O
either a vacuum or gas
A ____ is an enclosure designed either for surface or flush mounting and provided with a frame, mat, or trim in which a swinging door or doors are or may be hung.
cabinet
panel board
cutout box
switchboard
Of the following ____ is a false statement.
The term kilowatt indicates the measure of power which is all available for works
The term kilovolt-amperes indicate the apparent power made up of an energy component and a wattles or induction components
In an industrial plant, low power factor is usually due to underloaded induction motors.
The power factor of a motor is much greater at partial loads than at full load
A requirement of service that demands operation for alternate intervals of (1) load no load; or (2) load and rest; or (3) load, no load, and rest is called ____ duty.
variable
intermittent
short-time
periodic
An outlet where one or more receptacles are installed is called a _____.
multi-outlet assembly
receptacles outlet
duplex outlet
tri-plex outlet
A conductor encased within material of composition or thickness not recognized by the Code is a _____ conductor.
coated
semi
covered
fiber optic
Cooling of electrical equipment within enclosure is _____.
the responsibility of the equipment manufacturer
not covered by the Code
covered by the Code
not required
Approved is ______.
listed and labeled equipment
acceptable to the authority having jurisdiction
tested and approved for the purpose by a qualified testing lab
UL listed only
A system which will automatically furnish lighting and/or power to specified areas and/or equipment when there is a failure of the normal supply is known as a (an) _____ system.
fail safe
emergency
alarm
service safe
What chapter in the Code is Mobile Homes referred to?
Chapter 3
Chapter 5
Chapter 8
Chapter 9
Is it permissible to install direct current and alternating current conductors in one pull box?
Yes, if insulated for the maximum voltage of any conductor
No, never
Yes, if ampacity is the same for both conductors
Yes, in dry places
The maximum size fuse to be used in a branch circuit containing no motors depends on the _____.
load
wire size
voltage
switch size
The type letter for moisture-resistant thermoset is _____.
RUH
THW
RHW
MHR
On Edison 3-wire system, some incandescent lamps are observed to be brighter, and others to be dimmer, than normal. What is the most likely trouble?
weak breaker
loose fuse
poor neutral connection
too much voltage drop
A current-limiting overcurrent protective device is a device which will _____ the current flowing in the faulted circuit.
reduce
increase
maintain
none of these
The conductors and equipment for delivering energy from the electricity supply, system to the faulted circuit.
primary
distribution
main supply
service
Concealed is _____.
not readily visible
made inaccessible by the structure or finish of the building
surrounded by walls
attached to the surface
Continuous load is _____.
a load where the maximum current is expected to continue for three hours or more
a load where the maximum current is expected to continue for one hour or more
intermittent operation in which the load condition are regularly recurrent
operation at a substantially constant load for an indefinitely long time
If a live conductor is contacted accidentally the severity of the electrical shock is determined primarily by _____.
whether the current is AC or DC
the current in the conductor
the size of the conductor
the contact resistance
Electron flow produced by means of applying a pressure to a material is called _____.
thermoelectricity
piezoelectricity
electrochemistry
photo conduction
A dual voltage motor will run more efficiency ___.
at the lower voltage
at the higher voltage
the same at either voltage
none of these
the term anode refers to _____.
capacitor
dynamo
rectifier
inductor
A box contains one grounded and three undergrounded conductors, from one undergrounded to the grounded conductor 208 volts is measured, the other two undergrounded measure 120 volts to the grounded conductor, the system is ______.
delta
wye 3-wire
wye 4-wire
open delta 4-wire
The voltage drop in a line can be decreased by ____.
i. Increasing the resistance
ii. Increasing the current
iii. Increasing the load
iv. Increasing the wire size
III only
I and II only
III and IV only
I, III and IV only
A 10 ohm resistance carrying 10 amperes of current uses ____ watts of power.
100
20
500
1000
When using#12-2 with ground, the ground _____ carry current under normal operation.
will
will not
will sometimes
none of these
A transformer is more efficiency utilized when the load has a ____ power factor.
low
medium
average
high
When re-routing conduit, it may be necessary to increase the wire size if the distance is considerably greater, in order ______.
to account for current drop
to allow for possible resistance drop
to compensate for voltage drop
to increase mechanical strength
To handle 3-phase unbalanced system, balanced the system by making all loads equal to the ___single phase load.
smallest
average
largest
unbalanced
The connection between the grounded circuit conductor and the equipment grounding conductor all the service is called the _____.
equipment bonding jumper
main bonding jumper
circuit bonding jumper
electrode bonding jumper
Connection of conductors to terminal parts must ensure ______.
a good connection without damaging the conductor
proper torque values
proper bonding
proper crimping pressure
To determine directly whether all finished wire installations possess resistance between conductors, and between conductors and ground, use______.
set screws
shields
clamps
a megger
Most electric power tools, such as electric drills, come with a third conductor in the power lead which is used to connect the case of the tool to a grounded part of the electric outlet. The purpose for having this extra conductor is to ______.
protect the user of the tool should the winding break down to the case.
eliminate sparkling between the tool and the material being work upon.
provide for continued operation of the tool should the regular grounded line-wire open.
prevent accumulation of a static charge on the case.
The purpose of having a rheostat in the field of a DC shunt motor is to _____.
control the speed of the motor
minimize the starting torque
limit the field current to a safe value
reduce sparkling at the brushes
You are to check the power factor of the load, you cannot get a power factor meter, you would use _____.
a wattmeter
a voltmeter and a ammeter
a kilo-watt hour meter
an ammeter, a wattmeter and a voltmeter
The power factor which will have the least effect on the voltage at the most distant point from the source of supply for a two wire circuit is ______.
whether the supply is 25 cycle or 60 cycle AC
whether the supply is 25 cycle or 60 cycle AC
the amount of the load on the circuit
the length of the circuit
The load side is usually wired to the blades of a knife switch to ____.
prevent blowing the fuse when opening the switch.
make the blades dead when the switch is opened.
prevent arcing when the switch is opened.
allow changing of fuse without opening the switch
High voltage cable which is to be installed in underground ducts is generally protected with a ____.
outlet outer jacket
lead sheath
steel wire armor
tarred jute covering
A conduit coupling is sometimes tightened by using a strap wrench rather than a Stillson wrench, the strap wrench is used when it is important to avoid _____.
crushing the conduit
crushing the conduit
stripping the threads
damaging the outside finish
The life of insulation used in electrical installation is directly affected by heat, Of the following, the electrical insulation which can least withstand heat is ______.
mica
rubber
fiberglass
enamel
With respect to a common light bulb, it is correct to state that the _____.
circuit voltage has a no effect on the life of the bulb
base has a left hand thread
filament is made of carbon
lower wattage bulb has the higher resistance
One identifying feature of a squirrel cage induction motor is that it has no ______.
air gap
commutator or slip rings
iron core in the rotating part
winding on the stationary part
What is the voltage between point Y and Z?
72 volts
120 volts
24 volts
144 volts
In the sketch above, what is the wattage of the 20 ohms load?
120 watts
48 watts
144 watts
720 watts
