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48 Cards in this Set
- Front
- Back
3-1A1
The product of the readings of an AC voltmeter and AC anmeter is called: |
Apparent Power
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3-1A2
What is the basic unit of electrical power? |
Watt
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3-1A3
What is the term used to express the amount of electrical energy stored in an electrostatic field? |
Joules
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3-1A4
What devices is used to store electrical energy in an electrostatic field? |
Capacitor
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3-1A5
What formula would determine the inductive reactance of a coil if frequency and coil inductance are known? |
XL = 2f L
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3-1A6
What is the term for the out-of-phase power associated with inductors and capacitors? |
Reactive Power
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3-2A1
What determines the strength of the magnetic field around a conductor? |
The amount of current
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3-2A2
What will produce a magentic field? |
The current flowing through a conductor
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3-2A3
When induced currents produce expanding magnetic fields around conductors in a direction the opposes the original magnetic field, this is known as? |
Lenz's Law
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3-2A4
The opposition to the creation of magnetic lines of force in a magnetic circuit is known as: |
Reluctance
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3-2A5
What is meant by the term "back EMF"? |
A voltage that opposes the applied EMF
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3-2A6
Permeability is defined as: |
The ratio of magnetic flux density in a substance to the magnetizing force that produces it
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3-3A1
What metal is usually employed as a sacrificial anode for corrosion control purpose? |
Zinc bar
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3-3A2
What is the relative dielectric constant for air? |
1
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3-3A3
Which metal object may be the least affected by the galvanic corrosion when submerged in seawater? |
Stainless steel propeller shaft
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3-3A4
Skin effect is the phenomenon where: |
RF current flows in a thin layer of the conductor, closer to the surface, as frequency increases
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3-3A5
Corrosion resulting from electric current flow between dissimilar metals is called: |
Galvanic corrosion
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3-3A6
Which of these will be most useful for insulation at UHF frquencies? |
Mica.
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3-4A1
What formula would calculate the total inductance of the inductors in series? |
LT = L1 + L2
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3-4A2
Good conductors with minimum resistance have what type of electrons? |
Many free electrons
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3-4A3
Which of the 4 groups of metals listed below are the best low-resistance conductors? |
Gold, Silver, and Copper
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3-4A4
What is the purpose of a bypass capacitor? |
It removes alternating current by providing a low impedance path to ground
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3-4A5
How would you calculate the total capacitance in parallel? |
CT = C1 + C2 + C3
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3-4A6
How might you reduce the inductance of an antenna coil? |
Reduce the number of turns
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3-5A1
What are the most commonly used specifications for a junction diode? |
Maximum forward current and PIV (peak inverse voltage)
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3-5A2
What limits the maximum forward current in a junction diode? |
The juction temperature
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3-5A3
MOSFETs are manufactured with THIS protective device built into gate to protect the device from static charge and excessive voltage: |
Zener diode
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3-5A4
What are the two basic types of junction field-effect transistors? |
N-channel and P-channel
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3-5A5
A common emitter amplifier has: |
More voltage gain than a common collector
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3-5A6
How does the input impedance of a field-effect transistor compare with that of a bipolar transistor? |
An FET has high input impedance; a bipolar transistor has low input impedance
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3-6A1
An AC anmeter indicates: |
Effective (RMS) values of current
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3-6A2
By what factor must the voltage of an AC circuit, as indictated on the scale of an AC voltmeter, be multiplied to obtain the peak voltage value? |
1.414
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3-6A3
What is the RMS voltage at a common household electrical power outlet? |
117-V AC
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3-6A4
What is the easiest voltage amplitude to measure by viewing a pure sine wave signal on an oscilloscope? |
Peak-to-peak
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3-6A5
By what factor must the voltage measured in an AC circuit, as indicated on the scale of an AC voltmeter, be multiplied to obtain the average voltage value? |
0.9
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3-6A6
What is the peak voltage at a common household electrical outlet? |
165.5 volts
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3-7A1
What is a sine wave? |
A wave whose amplitude at any given instant can be represented by the projection of a point on a wheel rotating at a uniform speed
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3-7A2
How many degrees are there in one complete sine wave cycle? |
360 degrees
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3-7A3
What type of wave is made up of sine waves of the functional frequency and all the odd harmonics? |
Square
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3-7A4
What is the description of a square wave? |
A wave that abruptly changes back and forth between two voltage levels and stays at these levels for equal amounts of time
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3-7A5
What type of wave is made up of sine waves at the fundamental frequency and all the harmonics? |
Sawtooth wave
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3-7A6
What type of wave is characterized by a rise time significantly faster than the fall time (or vise versa)? |
Sawtooth wave
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3-8A1
What term is used to identify an AC voltage that would cause the same heating in a resistor as a corresponding value of DC voltage? |
Root mean square (RMS)
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3-8A2
What happens to reactive power in a circuit that has both inductors and capacitors? |
It alternates between magnetic and electric fields and is not dissipated
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3-8A3
Halving the cross-sectional area of a conductor will: |
Double the resistance
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3-8A4
Which of the following groups is correct for listing common materials in order of descending conductivity? |
Silver, copper, aluminum, iron, and lead
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3-8A5
How do you compute true power (power dissipated in the circuit) in a circuit where AC voltage and current are out of phase? |
Multiply apparent power times the power factor
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3-8A6
Assuming a power source to have a fixed value of internal resistance, maximum power will be transferred to the load when: |
The load impedance equals the internal impedance of the source
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