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AVI135
Electricity 2
108
Aviation
Undergraduate 1
03/17/2015

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Term
Electricity in which the flow of electrons periodically reverses in direction and continually changes in magnitude
Definition
Alternating Current
Term
Current starts at zero and builds up to a maximum in one direction, falls back to zero, builds up to a maximum in the opposite direction, and returns to zero
Definition
Alternating Current
Term
Advantages of Alternating Current
Definition
Ease with which it may be generated. All aircraft DC generators actually produce AC, but it is converted to DC before leaving the generator
Term
The AC waveform produced by a rotary generator
Definition
Sine Wave
Term
Sine wave AC has a constantly changing, periodically reversing and cyclically repeating set of values. One complete set of these variations, from zero to a maximum in the positive direction, back to zero, then to a maximum value in the opposite direction and back to zero, is one cycle of AC
Definition
Cycle
Term
One half of a cycle, or the positive or negative variation of a cycle of AC
Definition
Alternation
Term
The maximum value of current or voltage measured from the zero reference line
Definition
Peak Value
-The negative values will be exactly the same as the positive values, with the polarities being the only difference
Term
What do you multiply the effective value to get peak value?
Definition
1.414
Term
The maximum difference between the peak positive voltage or current , and the peak negative value
Definition
Peak to Peak Value
Term
This is the value measured when using an oscilloscope, and is important for determining the voltages which must be withstood by wiring installations
Definition
Peak to Peak Value
Term
electricity
Definition
A force caused by electrons moving from one atom to another
Term
a deficiency of electrons
Definition
positive charge
Term
excess of electrons
Definition
negative charge
Term
the difference in electrical charges causes
Definition
electrical pressure
(Voltage)
Term
A type of circuit in an electrical system in which all the components are connected in such a way that they provide only one path from the source of current flow, through all of the components, and back to the source.
Definition
Series Circuit
Term
The total _____ is equal to the sum of all the individual resistors
Definition
Resistance
Term
All the _____ in a series circuit must flow past every point in the circuit
Definition
Current
Term
The total ______ drops in a series circuit will total the voltage applied
Definition
Voltage
Term
A circuit in which there is more than one complete path for electrons to pass from the negative terminal of the power source back to its positive terminal
Definition
Parallel Circuit
Term
The total ____ is equal to the sum of the current in each branch of the circuit
Definition
Current
Term
The ____ drop across each branch of a parallel circuit is equal to each branch
Definition
Voltage
Term
The total _____ in a parallel circuit is equal to the reciprocal of the sum of reciprocals.
Definition
Resistance
Term
The rules of series circuits apply to the _____ portion.
Definition
Series
Term
The rules of parallel circuits apply to the _____ portion.
Definition
Parallel
Term
electronic circuits which operate as switches
Definition
Digital circuits
Term
The _____ consists of voltage levels that are changing back and forth between HIGH and LOW level or states
Definition
Digital waveform
Term
Most _____ in digital systems are made up of a series of pulses, sometimes referred to as pulse trains, and can be classified as either periodic or non-periodic
Definition
waveforms
Term
Periodic waveform in which each interval between pulses (the period) equals the time for one bit
Definition
Clock
Term
The two numbers in the binary systems, 1 and 0, are called bits, which is a combination of the words ___ and ___.
Definition
Binary Digits
Term
The number system whose base is two. It uses only two value, zero and one
Definition
Binary Numbering System
Term
an electron control valve that has most of the air removed from the glass or metal envelope in which the electrodes are mounted
Definition
Vacuum Tubes
Term
An electronic component that controls the flow of electrons without the use of heated filaments, vacuum spaces or moving parts
Definition
Solid state device
Term
A two element electrical device and acts as an electron check valve
Definition
Semiconductor Diodes
Term
A diode contains a ____ and a cathode
Definition
anode
Term
Due to the number of electrons in the valence shell and the strong covalent bonds formed when the electrons form a bond in one atom to another, neither ___ or ____ conduct eletricity
Definition
silicon ; germanium
Term
___, ____,and____ have only three valence electrons, and when one of these materials are doped with silicon or germanium, there are areas where the covalent bond cannot form due to the shortage of electrons
Definition
boron, indium, and gallium
Term
The _ type and _ type materials are joined either by a junction or a point of contact to form a semiconductor diode
Definition
N ; P
Term
Uses a single diode in series with an AC source and a load
Definition
Half Wave Rectifier
Term
Contains two diodes that change both halves of an AC cycle into DC (more efficient and produces smoother output)
Definition
Full wave rectifier
Term
The two diode full wave rectifier produces output voltage through only one half of the secondary (uses 4 diodes which are arranged in a ___ circuit)
Definition
bridge- type rectifier ; bridge
Term
Conducts in the reverse biased condition when a specific voltage is placed across the diode. Is connected in the circuit with the anode connected to the negative terminal, or the reverse biased condition
Definition
Zener Diodes
Term
A forward biased diode, electrons cross the junction and fall into holes/ As electrons fall into the valence band, they radiate energy/ Longer life, lower voltage, less heat
Definition
Light Emitting Diode (LED)
Term
The source of high voltage electronic energy, used to produce the spark to ignite the fuel-air mixture inside the cylinder of a reciprocating engine. Is an AC generator with a set of breaker points to interrupt the current the instant the spark is needed
Definition
Magneto
Term
A mechanical device consisting of a conductor being turned within a magnetic field, used to produce electricity by electromagnetic induction
Definition
Generator
Term
The force that causes electrons to move from one atom to another within an electrical circuit. The difference in electrical pressure or potential that exists between two points
Definition
EMF (electromotive force)
Term
Extend the thumb, index finger, and the middle finger so they are at right angles to one another. (Thumb for conductor; Index for the magnetic flux; middle for the current flow)
Definition
Left Hand Rule
Term
A device hat turns mechanical energy into electrical energy by rotating coils of wire through a magnetic field. As the conductors in the coils cut across the lines of magnetic flux, a voltage is generated that causes current flow. (rotating coil; stationary field; brushes and commutator)
Definition
Generator
Term
A 3 phase generator with a built in 3 phase, solid state rectifier to change the AC into DC before it leaves the _____.
Definition
alternator
Term
The stationary part of the alternator (stationary armature; made up of coils of wire)
Definition
stator
Term
The rotating portion is referred to as the ___ (rotating field or magnet; permanent magnet; electromagnet)
Definition
rotor
Term
The electrical law explaining induced current.___ Law states that a current induced in a conductor cut by lines of magnetic flux flows in the direction opposite to that of the current which produced the lines of magnetic flux.
Definition
Lenz's Law
Term
The standard unit of inductance. It is the amount of inductance in which a current change of one ampere per second will induce a voltage of one volt
Definition
Henry
Term
The symbol for inductance is the letter ___ and is measured in Henrys
Definition
Term
The number of turns in a coil, spacing between the turns, and wire size determines what
Definition
coil inductance
Term
An inductor that filters out certain frequencies
Definition
chokes
Term
When AC with a frequency of 50 to 60 hertz is converted to DC, the output is the form of_____.
Definition
pulsating DC
Term
An ____ is placed in series with the load, the pulsating current induces a back voltage that smoothes out the pulsations
Definition
inductor
Term
P in electrical calculations- the amount of electrical power used when one ampere of current is forced through an electrical load under a pressure of one volt.
Definition
Watt

746 watts of electrical power is equal to one mechanical horsepower
Term
The complete path followed by electrons from the negative terminal of the source of electrical energy, through the electrical load, back to the positive terminal of the source
Definition
circuit
Term
The amount of current flowing in a circuit is directly proportional to the circuit voltage and inversely proportional to the circuit resistance is what law?
Definition
Ohm's Law
Term
The algebraic sum of all voltage drops in any closed circuit is equal to zero is what law?
Definition
Kirchhoff's Voltage Law
Term
The sum of current flowing away from any point in an electrical circuit is equal to the sum of the current flowing to that point is what law?
Definition
Kirchhoff's Current Law
Term
the ratio of true power to the apparent power is the ___ factor
Definition
power
Term
Once impedance is found, you can use Ohm's Law to determine ____
Definition
current
Term
To calculate ___ __, use Ohm's Law to multiple the total current by each value of resistance, capacitive and inductive reactance.
Definition
voltage drop
Term
____ ____ is the product of the source voltage times the total current
Definition
apparent power
Term
The angle whose cosine is the power factor. The cosine of .96 is 16". The current leads to the voltage by 16"
Definition
Phase angle
Term
The actual AC power in the circuit when phase is taken into account
Definition
True Power
Term
Using the pythagorean theorem, you can determine the length of the ____ or ____ vector
Definition
resultant ; impedance
Term
In a direct current circuit, a change in voltage causes a proportional change in current
Definition
Phase
Term
The maximum value of current or voltage measured from the zero reference line
Definition
Peak Value
- Effective voltage is multiplied by 1.414
Term
The maximum difference between the peak positive voltage or current, and the peak negative value
Definition
peak to peak value
-value measured when using an oscilloscope
Term
An infinite number of instantaneous voltage or current measurements were made for each half cycle of sine wave AC, and an average taken of these values, the average would be 0.637 times the peak value
Definition
Average Value
Term
0.707 times the peak value. The average of the peak value that can be used to determine the amount of effective voltage that is used to calculate the working voltage and current used in an AC circuit. Measured with a voltmeter
Definition
Effective or RMS value
Term
The ____ of an angle is the ratio of the length of the side of a right triangle opposite the angle and the hypotenuse
Definition
Sine
Term
The amount of time required for one cycle of events to take place. Aircraft AC having a frequency of 400Hz, has a ____ of 1/400 seconds
Definition
period
Term
The AC waveform produced by a rotary generator
Definition
Sine wave
Term
Sine wave AC has constantly changing, periodically reversing and cyclically repeating a set of values.
Definition
Cycle
Term
One half of a cycle, or the positive or negative variation of a cycle of AC
Definition
Alternation
Term
AC is generated due to the relationship of ___ and ____
Definition
magnetism ; electricity
Term
Anytime current flows in a conductor, a ___ ____ surrounds the conductor
Definition
magnetic field
Term
____ _____ is increased by increasing the strength of the magnetic field, increasing the number of turns of the conductor or by increasing the speed of movement of the conductor through the lines of flux
Definition
Electron flow
Term
Used when a high capacity with a low voltage is required
- Uses a thin dielectric of oxide film in between aluminum foil
Definition
Electrolytic Capacitors
Term
Changes one of the three factors that determine a capacitors ability to store electrons
Definition
variable capacitor
Term
most radio tuners change the plate area using a rotor made up of thin sheets of aluminum meshed together with a group of fixed plates called stators
Definition
plate area
Term
Large aircraft use variable capacitors to measure the amount of fuel on board
Definition
Fuel Quantity Transmitters
Term
The ____ are made up of two concentric tubes in the tank that extend from top to bottom. The tubes makes up the plates of a capacitor and the fuel acts as the dielectric
Definition
Transmitter
Term
-Uses 28 volts supplied and must step up the voltage
-A step up transformer and a set of points makes up a vibrator for the purpose to step up
-Supplies the stepped up voltage to a storage capacitor
Definition
Turbine ignition system
Term
A capacitors ability to store an electrical charge is measured in ___
Definition
farads
Term
The basic unit of ____. One farad is the amount of ____ that allows a charge of one coulomb to be stored under the pressure of one volt
Definition
capacitance
Term
C=?
Q=?
E=?
Definition
C- Capacity in Farads
Q- Charge in coulombs
E- Voltage in volts
Term
one ___ is typically too many electrons for practical use, so normally measured in micro___ or as a pico___
Definition
farad
Term
______ is affected by 3 variables:
1)area of the storage plates
2)separation between the plates
3) composition of the dielectric
Definition
capacity of a capacitor
Term
____ store energy in two forms
1) Electrostatic attraction
2) Distortion of the electron orbits within the dielectric material
Definition
Capacitors
Term
The ____ ____ is the frequency where inductive reactance and capacitive reactance are the same
Definition
Resonance Frequency
Term
_____ _____ is zero when the frequency is zero. However as frequency increases, so does _____ ____
Definition
Inductive Reactance
Term
____ ____ is infinite when the frequency is zero and decreases as frequency increase
Definition
Capacitive reactance
Term
"i" in electrical calculations
- a measure of electron (current) flow
-one ___ is equal to the flow of one coulomb (6.28 billion billion electrons) past a point in one second
-The amount of current that can be forced through one ohm of resistance by a pressure of one volt.
Definition
Ampere
Term
"E" in electrical calculations
-The basic unit of electrical pressure
-One volt is the amount of electrical pressure needed to force one amp of current through a resistance of one ohm.
-The amount of electrical pressure drop that occurs when a current of one amp produces one watt of power
Definition
Volt
Term
"R" in electrical calculations
- The characteristic of an electrical circuit that opposes the flow of electrons
-When electrons flow through a resistance, power is used, voltage is dropped, and heat is produced.
-Amount of resistance in ohms to produce a one volt drop when one amp of current is flowing through it
Definition
Ohm
Term
"P" in electrical calculations
-Measured in watts
-The product of the applied voltage and the current in a DC circuit
-The product of the applied voltage and only that portion of the current in phase with the voltage in an AC circuit
Definition
Power
Term
The negatively charged part of an atom of which all matter is made
Definition
Electron
Term
____ theory states that electricity moves from a negative source to a positive source.
Definition
electron theory
Term
-A material with 3 or less valance electrons
-Used to produce electrical ____s
- Gold, silver, aluminum copper
-When an electrical pressure is applied, and electron is forced to move from one atom to the next
Definition
conductor
Term
A force caused by electrons moving from one atom to another
Definition
electricity
Term
A deficiency of electrons is called a ___ ____, and an excess of electrons is called a ____ _____
Definition
positive charge; negative charge
Term
An imaginary flow of electricity said to go from the positive terminal of an electrical source to it's negative terminal is what theory?
Definition
Conventional Theory
Term
Which symbol points in the direction of current flow in the conventional theory?
Definition
The arrowhead of a semiconductor (diode) symobol
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