Final Test
What is the RMS value of an AC voltage that has a 480 V peak? A. 278.72 V B. 305.76 V C. 339.46 V D. 453.53 V
C. 339.46 V
Power input must equal power output, which enables the current rating for a winding to be determined. A. True B. False
A. True
The grounding prong of a plug should never be cut off or bypassed. A. True B. False
A. True
Three capacitors, a 12 μF, a 20 μF and a 30 μF, are connected in parallel. What is the total capacitance? A. 6μF B. 62 μF
B. 62 μF
What is the applied voltage is a series circuit with two resistors of 25 V and 60 V, respectively? A. 35 V B. 85 V C. 25 V D. 60 V
B. 85 V
An induced voltage opposes the motion that causes it according to _____. A. Ohm's Law B. Len's Law C. Coulomb's Theory D. Fleming's Rule
B. Len's Law
Man-made permanent magnets retain their magnetism _____ than natural magnets A. Less B. Longer
B. Longer
Moving coils farther apart increases the amount of __________. A. Magnetic Field B. Magnetic Flux Leakage C. Countervoltage D. True Power
B. Magnetic Flux Leakage
Polarized capacitor ______. A. Must be used with AC only B. Must be used with DC only C. Can be used with either AC or DC
B. Must be used with DC only
In a one-terminal zero-center voltmeter connected to ground and the probe connected to a Point A, the pointer of the voltmeter gives a _______ indication for voltage A. Positive B. Negative C. Neutralizing D. Stabilizing
B. Negative
Platinum, titanium, and chromium are examples of _____materials A. Ferromagnetic B. Paramagnetic C. Diamagnetic D. Permanent
B. Paramagnetic
A single electron moves at what speed? A. Rather Quickly B. Rather Slowly
B. Rather Slowly
Circuits that have more than one path for current flow are _____ circuits. A. Parallel B. Series C. Combination
A. Parallel
Which type of fuel cell require only hydrogen, oxygen from the air, and water to operate? A. Polymer electrolyte membrane fuel cells B. Phosphoric acid fuel cells C. Solid oxide fuel cells D. Molten carbonate fuel cells
A. Polymer electrolyte membrane fuel cells
What induces a voltage in the secondary for transformer? A. Primary Current B. Secondary Current C. Polarity D. Current
A. Primary Current
The time required for current in an inductor to reach its full Ohm's law value is called the ______ time constant A. R-L B. R^2 C. R-C D. L-R
A. R-L
Refer to the diagram. Through what must all the current in the circuit flow? (Left light = R1, Middle light = R2, Right light = R3) A. R1 B. R2 C. R3 D. Point B
A. R1
The statement, "In a DC circuit, the current is directly proportional; to voltage and inversely proportional to resistance," is known as ____ law. A. Ampere's B. Coulomb's C. Ohm's D. Volt's
C. Ohm's
When a magnetic material's molecules are lined up; and increases in current flow no longer cause increases in magnetic field strength, the material has reached ____ A. Permeability B. Reluctance C. Saturation D. Residual Magnetism
C. Saturation
Rotating machines normally produce a waveform called a _____ wave A. Cosine B. Linear C. Sine D. Pulsating
C. Sine
A foot-pound, which is the amount of force required to raise a 1-pound weight 1 foot, is known as what? A. British Thermal unit B. Joule C. Voltage D. Horsepower
D. Horsepower
The three substances that form natural magnet are ______ A. Iron, boron, and cobalt B. Copper, iron, and cobalt C. Copper, nickel, and boron D. Iron, nickel, and cobalt
D. Iron, nickel, and cobalt
What does EL(load) represent? A. Phase current of the load B. Phase voltage of the Alternator C. Phase voltage of the load D. Line voltage of the load
D. Line voltage of the load
AN electrical circuit has a voltage of 50 V and a resistance of 5 Ω. What is the value of current? A. 10 A B. 45 A C. 55 A D. 250 A
A. 10 A
An electric motor is running on 120 V. The current is measured to be 2 A. How many Ohms of resistance is the motor? A. 60 B. 118 C. 122 D. 240
A. 60
Parallel circuit are also called ______ A. Current Dividers B. Current Multipliers C. Voltage Dividers D. Voltage Multipliers
A. Current Dividers
Each complete waveform of 360 degrees is called a _____. A. Cycle B. Hertz C. Frequency D. Rotation
A. Cycle
In the combination circuit, what must the same current flow through? (Left R1 then R2, Right R3 then R4) A. R1 and R2 B. R1 and R3 C. R1 and R4 D. Point A and R1
A. R1 and R2
A combination circuit contains both series and parallel elements A. True B. False
A. True
The product- over- sum formula can be used only when all the resistors in the circuit are of equal value A. True B. False
B. False
Any transformer flux that does not follow the core and escapes into the surrounding air is called _____. A. Magnetizing Flux B. Flux Coupling C. Flux Leakage D. Flux Reactance
C. Flux Leakage
In standard metric prefixes, what is the first step above the base unit? A. Deka B. Hecto C. Kilo D. Centi
A. Deka
A three-phase connection in which three separate inductive loads have been connected together is a(n) _______ connection A. Delta B. Wye C. Open Delta D. Open Wye
A. Delta
Energy in a capacitor is stored as a(n) ______. A. Electrostatic Charge B. Magnetic Field C. Electromagnetic Field D. Circulating Current
A. Electrostatic Charge
The advantage of _______ is that less current is required to produce the same amount of power. A. High-Voltage transmission B. Low-Voltage transmission C. High-Voltage DC D. Low-Voltage DC
A. High-Voltage transmission
In a three-phase connection, what is the voltage measured between the lines? A. Line voltage B. Phase voltage
A. Line voltage
Which of the following metals would accept electrons more easily than the other listed? A. Lithium B. Zinc C. Tin D. Silver
A. Lithium
Solar cells constructed from a combination of P- and N- type ____ materials. A. Semiconductor B. Conductor C. Resistor D. Semiresistor
A. Semiconductor
I calculating apparent power (VA) in a three-phase circuit, the phase values of voltage and current are multiplied by ______. A. Three B. Four C. Five D. Six
A. Three
A node is a junction point where the current splits when reached A. True B. False
A. True
Because a circuit breaker is connected in a series with the rest of the circuit, all the circuit current must flow through them A. True B. False
A. True
Because only one path exists for the current top flow through a series circuit, it must flow through each resistor in the circuit A. True B. False
A. True
Because the current and voltage are both either positive or negative at the same time, watts is always positive A. True B. False
A. True
Color bands and dots on a dipped tantalum capacitor determine the value, tolerance, and voltage. A. True B. False
A. True
Connecting the batteries or cells in parallel has the effect of increasing the area of the plates A. True B. False
A. True
If current is flowing in a circuit containing an inductor and the power switch is opened, the magnetic field surrounding the inductor collapses and induces voltage into the inductor, resulting in a voltage spike. A. True B. False
A. True
Lithium cells can have voltages that range from 1.9 volts to 3.6 volts A. True B. False
A. True
Motor loads appear to be resistive because there is a conversion of electrical energy into mechanical energy A. True B. False
A. True
One factor that determines inductance is how far the windings are separated from each other. A. True B. False
A. True
One of the rules for Ohm's law when finding values of voltage, current, resistance, and power in a series circuit is that the current is the same at any point in the circuit A. True B. False
A. True
The polarity of the field is a speaker is determined by the direction of current flow A. True B. False
A. True
There are two theories concerning current flow, electron flow theory and conventional current flow theory. A. True B. False
A. True
Tracing the current path n a combination circuit will identify the series and parallel elements. A. True B. False
A. True
Transformer impedance is determined by the physical construction of the transformer. A. True B. False
A. True
When the primary of a transformer is connected to power but there is no load connected to the secondary, current is limited by the inductive reactance of the primary. A. True B. False
A. True
In a series circuit, the_____ is the same at any point in the circuit A. Resistance B. Current C. Voltage Drop
B. Current
When determining the amount of capacitance needed to correct power factor, what is the first step? A. Determine the capacitance value of each capacitor B. Determine the reactive power of the circuit C. Determine the apparent power of the circuit D. Determine the power of the circuit
B. Determine the reactive power of the circuit
A lesser amount of current will flow through a low-value resistor, and a greater amount of current will flow through a high-value resistor A. True B. False
B. False
Current can rise instantly through an inductor A. True B. False
B. False
DC loads are generally described as being resistive, inductive, or capacitive, depending on the phase-angle relationship of the voltage and current and amount of true power produced by the circuit A. True B. False
B. False
During normal operation of a typical 120-volt appliance circuit, current flows through the hot, grounding, and neutral conductors. A. True B. False
B. False
In a speaker, when the electromagnet has a south polarity, it is repelled from the permanent magnet A. True B. False
B. False
The nameplate lists the current rating of the windings A. True B. False
B. False
The peak-to-peak value of a sine wave is measured from the minimum value in the negative direction to the maximum value in the positive direction A. True B. False
B. False
To solve the unknown values in a parallel circuit, use series circuit rules for those sections of the circuit that are connected in parallel circuit. A. True B. False
B. False
Using Ohm's law chart, power can be found when voltage and current are known, represented by E= I*R A. True B. False
B. False
With the JAN standard of capacitor markings, the fourth dot indicates classes A to E of temperature and leakage coefficients A. True B. False
B. False
What is the basic unit of capacitance? A. Henry B. Farad C. Ohms D. Coulomb
B. Farad
Increasing the surface area of the plates will cause the capacitance of a capacitor to _________________. A. Decrease B. Increase C. Stay the same
B. Increase
In the image the magnet is moved toward the coil. What happens to the magnetic field around the coil? A. It collapses inward of the coil, inducing a voltage in the coil B. It expands outward of the coil, inducing a voltage in the coil C. It collapses outward of the coil, inducing a voltage in the coil D. It expands inward of the coil, inducing a voltage in the coil
B. It expands outward of the coil, inducing a voltage in the coil
Which of the following is the current divider formula? A. I1 = ET/R1 B. Ix = (RT/Rx)*IT C. RT = R/N D. RT = (R1*R2)/(R1+R2)
B. Ix = (RT/Rx)*IT
Which side has more inductance? A. Left side B. Right side
B. Right side
What type of cell can be recharged? A. Primary B. Secondary
B. Secondary
What is a measure of the amount of acid contained in water? A. Relative Gravity B. Specific Gravity C. Relative Resistance D. Specific Resistance
B. Specific Gravity
Line current and phase current are the same in the ____ configuration A. Delta B. Wye
B. Wye
The three-phase connection in which one end of each of the windings are connected together is called a(n) A. Delta B. Wye C. Open Delta D. Open Wye
B. Wye
The amplitude of a waveform is measured from ____ A. Peak to Peak B. Zero to the highest value obtained in either direction C. Zero to the RMS level D. Zero to the effective level
B. Zero to the highest value obtained in either direction
Assume a total current of 2 amperes flows in a circuit with three resistors. R1 has a value of 1000 ohms, R2 has a value of 240 ohms, and a value of 300 oms, producing a total resistance of 80 ohms for the circuit. What is the amount of the current flow through resistor R3? A. 0.16 B. 0.67 C. 0.53 D. 0.24
C. 0.53
The horsepower rating of three-phase motors and the kilovolt-ampere rating of three-phase transformers are about _____ greater than for single-phase motors or transformers with a similar frame size. A. 75% B. 100% C. 150% D. 200%
C. 150%
What is the drop voltage across each resistor in a 24-volt battery that has four resistors? A. 3 B. 4 C. 6 D. 8
C. 6
A combination circuit is a circuit that contains _______ A. Only series components B. Only parallel components C. Both series and parallel components D. both voltage and current sources
C. Both series and parallel components
What typically used to help eliminate voltage spikes and surges? A. Rods B. Insulators C. Capacitors D. Inductors
C. Capacitors
Polarized capacitors are also known as ____ capacitors. A. Bipolar B. Variable C. Electrolytic D. Electoplated
C. Electrolytic
The important factors concerning _____ are a conductor, a magnetic field, and relative motion A. Exponential curve B. Lenz's Law C. Electromagnetic induction D. Induced voltage
C. Electromagnetic induction
As current increases, a magnetic field ______ around the inductor, inducing a voltage into the coil A. Charge B. Compresses C. Expands D. Constricts
C. Expands
What letter symbolizes the farad? A. C B. Q C. F D. V
C. F
When a closed loop of wire cuts through magnetic flux lines, a current is induced into the loop. The current in the loop sets up a magnetic field that is in opposition to the original magnetic flux. This is essentially _____. A. Coulomb's Law B. Ohm's law C. Lenz's law D. Weber's law
C. Lenz's law
The velocity of AC through a conductor is ____ the speed of light A. Equal to B. Greater than C. Less than
C. Less than
In engineering notation, what is the third prefix below the base unit as? A. Milli B. Micro C. Nano D. Pico
C. Nano
In a DC circuit, the product of volts times the amperes is called the _____ power. A. Apparent B. Reactive C. True D. Inductive
C. True
In the MKS or SI system, 1 ampere-turn equals how many gilberts? A. 0.7905 B. 1.256 C. 0.1555 D. 1.256637
D. 1.256637
A delta-connected three-phrase alternator is driving a wye-connected resistive load. The alternator output voltage is 480 V. Load resistors are 12 Ohms each. What is the phase current in the alternator? A. 13.33 A B. 23.09 A C. 39.28 A D. 40 A
D. 40 A
Load 1 consists of three resistors with a resistance of 6 ohms each, connected in wye and the phase voltage is less than the line voltage by a factor of 1.732. What is the phase current? A. 56 A B. 96.992 A C. 40.416 A D. 53.888 A
D. 53.888 A
A(n) ______ battery is a lead-acid battery that does not spill sulfate or degrade like common flooded cell battery A. Sealed Lead-Acid B. Alkaline-Manganese C. Lithium D. Absorbed Glass Mat (AGM)
D. Absorbed Glass Mat (AGM)
In series circuits, the _____ voltage is equal to the sum of the voltage drops across all the resistors A. Parallel B. Voltmeter C. Total D. Applied
D. Applied
The conductor offers some amount of ohmic resistance to the flow of electrons, depending on the type of material from which the conductor is made, its length, and its _______ A. Time Constant B. Frequency C. Magnitude D. Diameter
D. Diameter
A voltage _____ is used to provide different voltages between certain ppoints in a circuit A. Doubler B. Multiplier C. Scalar D. Divider
D. Divider
What does the diagram depict? A. Total Voltage B. Voltage Surge C. Voltage Spike D. Exponential Curve
D. Exponential Curve
I= VA/E What would be calculated by using the above formula? A. Maximum current of the secondary B. Maximum current of the primary C. Transformer power D. Full-Load current rating of the secondary winding
D. Full-Load current rating of the secondary winding
Which of the following is a secondary cell? A. Alkaline B. Mercury C. Edison-Lalande D. Nickel-Cadmium
D. Nickel-Cadmium