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Voltage is represented by what letter?
V
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Charge represented by what letter?
Q
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The rate of electron flow in an electrical circuit is what?
Current
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The amount of electron crowding refers to what?
Current density
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energy is the product of what?
Power and time
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Define power?
Rate of doing work
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Passive and active elements of a circuit consume or use what?
Energy
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What type of circuit is not carrying any current?
Open
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Large Load circuits require what type of disconnects?
Manual
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How do alternate action and momentary switches differ?
Momentary switches returned home after release
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What switches can be used to switch between more than 2 circuits?
Rotary switches
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What switches are used to detect hydraulic oil levels?
Reed switches
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What is the positive terminal of a diode known as?
anode
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What type of bias is it when a diode is connected in the proper polarity as current passes through it?
forward
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The output of a transistor is known as a what?
Emitter
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What is an example of a analog IC?
Electronic voltage regulator
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Digital ics are used in binary processes and what?
Calculations
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electricity is applied to what of a solenoid?
Coil
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Linear force of a solenoid is determined by what?
Number of turns in the coil
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Electricity travels at what speed?
Speed of light
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When a materials electrons have become aligned and creates a force external to its self it is called a what?
Magnet
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When a loop of wire is rotated between the poles of a magnet what are made to flow through the wire?
Electrons
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What allows the generation of pulsing direct current?
Commutator
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when comparing flow of electricity through a wire to water flowing through a pipe what is similar to the water pressure?
Voltage
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How many times does AC current reverse its polarity each cycle?
Twice
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Passing a conductor through magnetic field in generating a current is known as what?
Inducing a current
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One magnet is made to turn inside of another magnet in a motor by switching what of the turning magnet?
Poles
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Instead of using a permanent magnet to generate a stationary magnetic field most motors use what?
Field coils
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What does the stator consist of?
Core and winding inside the motor
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The magnet that turns inside the motor is called the what?
Rotor
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A motor that runs on AC or DC is a what kind of motor?
Universal
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The device used to change the voltage level of alternating current is a what?
Transformer
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Atoms bind together in a molecule using ________ energy.
chemical
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________ is the force developed by a motor and applied to a shaft.
Torque
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What is the method used to start a DC generator turning?
Primemover
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What are the three causes of overheating ball bearings?
- overpacked grease
- improper lubrication
- misalignment
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What is defined as an electrical connection between the wiring of a motor and its metal frame work?
Ground
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Dust and foreign particles are cleaned from electrical equipment while limiting damage to electrical components by what?
vacuum
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What type of AC single phase motors will also operate on direct current?
Series wound
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What is used aboard ships with AC generators to step-up or step-down voltage?
transformers
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The reversal of an AC, three phase, induction motor is accomplished by what?
Interchanging the leads
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If the frequency is reduced from 60 to 55 hertz on a 120/240 volt three phase motor, the motor would what?
slow down
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On a diesel electric plant, raising the field excitation will cause the DC propulsion motor to what?
increase in speed
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Adding resistance in series with field winding of a DC shunt motor without a load, will cause the motor speed to what?
increase
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The item referred to as a pigtail on a DC motor brush rigging is a what?
uninsulated wire
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The electrolyte used in a nickel cadmium battery is distilled water and what?
potassium hydroxide
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The number of cells in a 12 volt lead acid battery is what?
6
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What is the electrolyte in a lead acid storage battery?
distilled water and sulfuric acid
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What is the formula to calculate MMF?
Amps x Number of turns = Ampere turns
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The opposition to the establishment of magnetic lines of force in a magnetic circuit is the circuits _________.
reluctance
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All of the conductors in a DC series circuit have the same what?
current
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The total voltage of a series circuit is the ____________.
sum of individual voltage drops
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The total power used up in a series circuit is __________.
sum of the powers used
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What are the components of a fluorescent lighting system?
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The source of emergency lighting and power at loss of normal ships power on a cargo vessel should be obtained from the what?
Emergency generator to emergency switch board
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The voice signal generated by a sound powered phone transmitter is proportional to what?
Amplitude and frequency striking the diaphragm.
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Main engine room control console alarms are to be of the self monitoring type, meaning that an open circuit to a particular alarm circuit will what?
cause an alarm
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When the console indicating lamp burns out, attempt to renew it should not be made while maneuvering because why?
it can cause a ground or short of a vital function
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What has an measurable effect on AC circuits?
Capacitors, inductors, resistors
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On a DC generator, a rheostat is connected in series with the shunt field to adjust what?
field current
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An AC generator output is generated in the what?
armature windings
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Contactors of a magnetic controller are operated by what?
electromechanical devices
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The current coil of a watt meter or ammeter must be connected how?
in series with the load
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What minimizes the stroboscopic effect of fluorescent lamps that operate on a 3 phase AC circuit?
Operate lamps at more than one phase
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What type of bearing are used in large propulsion generators and motors?
journal bearings
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What is an acceptable resistance reading for the ground connection between the ships hull and the metal frame of a portable drill?
less than 1 ohm
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What indicates ball bearing malfunction in operating machinery?
high temperatures and loss of speed
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Dirt, moisture, and oil in generator and motor ventilation ducts cause overheating by?
not allowing heat to dissipate
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What is the unit for capacitance?
farrad
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When field resistance is increased voltage will what?
decrease
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What is provided by the exciter on an AC generator?
Direct current to field windings
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What 3 steps are taken prior to working on a high voltage circuit?
- Remove power
- Discharge capacitors
- ground the circuit
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Aboard a ship, selective tripping does what?
Isolates faulty circuits
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AC generator frequency varies directly with what?
rotor speed
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What type of overload relays requires a time delay before resetting?
thermal
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What is the preferred method for cleaning motors and generators?
vacuum
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What is the minimum amount of electric current that can cause fatal shock?
10 milliamps
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What must occur to reverse propeller rotation in a diesel electric DC propulsion system?
Change polarity of generator terminal voltage
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What is the basis of electricity?
transfer of electrons
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What type of charge does an electron carry?
negative
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What is an example of a variable?
temperature
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What do coulombs measure?
charge
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What are the conditions necessary to produce electromotive force in a generator?
conductor capable carrying current moving in a magnetic field
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What is the phenomena of counter electromotive force?
Generator action in a motor
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Why do electrical contactors move when energized?
Magnetic lines of flux pull the movable permeable core into the coil
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