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116 Cards in this Set
- Front
- Back
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The product of the readings of an AC voltmeter and AC ammeter is called:
A. Apparent power. B. True power. C. Power factor. D. Current power. |
A. Apparent power.
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What is the basic unit of electrical power?
A. Ohm. B. Watt. C. Volt. D. Ampere. |
B. Watt.
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What is the term used to express the amount of electrical energy stored in an electrostatic field?
A. Joules. B. Coulombs. C. Watts. D. Volts. |
A. Joules.
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What device is used to store electrical energy in an electrostatic field?
A. Battery. B. Transformer. C. Capacitor. D. Inductor. |
C. Capacitor.
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What formula would determine the inductive reactance of a coil if frequency and coil inductance are known?
A. XL = f L B. XL = 2f L C. XL = 1 / 2f C D. XL = 1 / R2+X2 |
B. XL = 2f L
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What is the term for the out-of-phase power associated with inductors and capacitors?
A. Effective power. B. True power. C. Peak envelope power. D. Reactive power. |
D. Reactive power.
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What determines the strength of the magnetic field around a conductor?
A. The resistance divided by the current. B. The ratio of the current to the resistance. C. The diameter of the conductor. D. The amount of current. |
D. The amount of current.
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What will produce a magnetic field?
A. A DC source not connected to a circuit. B. The presence of a voltage across a capacitor. C. A current flowing through a conductor. D. The force that drives current through a resistor. |
C. A current flowing through a conductor.
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When induced currents produce expanding magnetic fields around conductors in a direction that opposes the original magnetic field, this is known as:
A. Lenz’s law. B. Gilbert's law. C. Maxwell’s law. D. Norton’s law. |
A. Lenz’s law.
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The opposition to the creation of magnetic lines of force in a magnetic circuit is known as:
A. Eddy currents. B. Hysteresis. C. Permeability. D. Reluctance. |
D. Reluctance.
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What is meant by the term “back EMF”?
A. A current equal to the applied EMF. B. An opposing EMF equal to R times C (RC) percent of the applied EMF. C. A voltage that opposes the applied EMF. D. A current that opposes the applied EMF. |
C. A voltage that opposes the applied EMF.
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Permeability is defined as:
A. The magnetic field created by a conductor wound on a laminated core and carrying current. B. The ratio of magnetic flux density in a substance to the magnetizing force that produces it. C. Polarized molecular alignment in a ferromagnetic material while under the influence of a magnetizing force. D. None of these. |
B. The ratio of magnetic flux density in a substance to the magnetizing force that produces it.
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What metal is usually employed as a sacrificial anode for corrosion control purposes?
A. Platinum bushing. B. Lead bar. C. Zinc bar. D. Brass rod. |
C. Zinc bar.
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What is the relative dielectric constant for air?
A. 1 B. 2 C. 4 D. 0 |
A. 1
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Which metal object may be least affected by galvanic corrosion when submerged in seawater?
A. Aluminum outdrive. B. Bronze through-hull. C. Exposed lead keel. D. Stainless steel propeller shaft. |
D. Stainless steel propeller shaft.
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Skin effect is the phenomenon where:
A. RF current flows in a thin layer of the conductor, closer to the surface, as frequency increases. B. RF current flows in a thin layer of the conductor, closer to the surface, as frequency decreases. C. Thermal effects on the surface of the conductor increase the impedance. D. Thermal effects on the surface of the conductor decrease the impedance. |
A. RF current flows in a thin layer of the conductor, closer to the surface, as frequency increases.
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Corrosion resulting from electric current flow between dissimilar metals is called:
A. Electrolysis. B. Stray current corrosion. C. Oxygen starvation corrosion. D. Galvanic corrosion. |
D. Galvanic corrosion.
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Which of these will be most useful for insulation at UHF frequencies?
A. Rubber. B. Mica. C. Wax impregnated paper. D. Lead. |
B. Mica.
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What formula would calculate the total inductance of inductors in series?
A. LT = L1 / L2 B. LT = L1 + L2 C. LT = 1 / L1 + L2 D. LT = 1 / L1 x L2 |
B. LT = L1 + L2
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Good conductors with minimum resistance have what type of electrons?
A. Few free electrons. B. No electrons. C. Some free electrons. D. Many free electrons. |
D. Many free electrons.
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Which of the 4 groups of metals listed below are the best low-resistance conductors?
A. Gold, silver, and copper. B. Stainless steel, bronze, and lead. C. Iron, lead, and nickel. D. Bronze, zinc, and manganese. |
A. Gold, silver, and copper
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What is the purpose of a bypass capacitor?
A. It increases the resonant frequency of the circuit. B. It removes direct current from the circuit by shunting DC to ground. C. It removes alternating current by providing a low impedance path to ground. D. It forms part of an impedance transforming circuit. |
C. It removes alternating current by providing a low impedance path to ground.
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How would you calculate the total capacitance of three capacitors in parallel?
A. CT = C1 + C2 / C1 - C2 + C3. B. CT = C1 + C2 + C3. C. CT = C1 + C2 / C1 x C2 + C3. D. CT = 1 / C1+1 / C2 + 1 / C3. |
B. CT = C1 + C2 + C3.
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How might you reduce the inductance of an antenna coil?
A. Add additional turns. B. Add more core permeability. C. Reduce the number of turns. D. Compress the coil turns. |
C. Reduce the number of turns.
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What are the two most commonly-used specifications for a junction diode?
A. Maximum forward current and capacitance. B. Maximum reverse current and PIV (peak inverse voltage). C. Maximum reverse current and capacitance. D. Maximum forward current and PIV (peak inverse voltage). |
D. Maximum forward current and PIV (peak inverse voltage).
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What limits the maximum forward current in a junction diode?
A. The peak inverse voltage (PIV). B. The junction temperature. C. The forward voltage. D. The back EMF. |
B. The junction temperature.
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MOSFETs are manufactured with THIS protective device built into their gate to protect the device from static charges and excessive voltages:
A. Schottky diode. B. Metal oxide varistor (MOV). C. Zener diode. D. Tunnel diode. |
C. Zener diode.
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What are the two basic types of junction field-effect transistors?
A. N-channel and P-channel. B. High power and low power. C. MOSFET and GaAsFET. D. Silicon FET and germanium FET. |
A. N-channel and P-channel.
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A common emitter amplifier has:
A. Lower input impedance than a common base. B. More voltage gain than a common collector. C. Less current gain than a common base. D. Less voltage gain than a common collector. |
B. More voltage gain than a common collector.
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How does the input impedance of a field-effect transistor compare with that of a bipolar transistor?
A. An FET has high input impedance; a bipolar transistor has low input impedance. B. One cannot compare input impedance without first knowing the supply voltage. C. An FET has low input impedance; a bipolar transistor has high input impedance. D. The input impedance of FETs and bipolar transistors is the same. |
A. An FET has high input impedance; a bipolar transistor has low input impedance.
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An AC ammeter indicates:
A. Effective (TRM) values of current. B. Effective (RMS) values of current. C. Peak values of current. D. Average values of current. |
B. Effective (RMS) values of current.
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By what factor must the voltage of an AC circuit, as indicated on the scale of an AC voltmeter, be multiplied to obtain the peak voltage value?
A. 0.707 B. 0.9 C. 1.414 D. 3.14 |
C. 1.414
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What is the RMS voltage at a common household electrical power outlet?
A. 331-V AC. B. 82.7-V AC. C. 165.5-V AC. D. 117-V AC. |
D. 117-V AC.
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What is the easiest voltage amplitude to measure by viewing a pure sine wave signal on an oscilloscope?
A. Peak-to-peak. B. RMS. C. Average. D. DC. |
A. Peak-to-peak.
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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?
A. 0.707 B. 1.414 C. 0.9 D. 3.14 |
C. 0.9
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What is the peak voltage at a common household electrical outlet?
A. 234 volts. B. 117 volts. C. 331 volts. D. 165.5 volts. |
D. 165.5 volts.
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What is a sine wave?
A. A constant-voltage, varying-current wave. B. 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. C. A wave following the laws of the trigonometric tangent function. D. A wave whose polarity changes in a random manner. |
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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How many degrees are there in one complete sine wave cycle?
A. 90 degrees. B. 270 degrees. C. 180 degrees. D. 360 degrees. |
D. 360 degrees.
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What type of wave is made up of sine waves of the fundamental frequency and all the odd harmonics?
A. Square. B. Sine. C. Cosine. D. Tangent. |
A. Square.
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What is the description of a square wave?
A. A wave with only 300 degrees in one cycle. B. A wave whose periodic function is always negative. C. A wave whose periodic function is always positive. D. A wave that abruptly changes back and forth between two voltage levels and stays at these levels for equal amounts of time. |
D. 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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7A5 What type of wave is made up of sine waves at the fundamental frequency and all the harmonics?
A. Sawtooth wave. B. Square wave. C. Sine wave. D. Cosine wave. |
A. Sawtooth wave.
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What type of wave is characterized by a rise time significantly faster than the fall time (or vice versa)?
A. Cosine wave. B. Square wave. C. Sawtooth wave. D. Sine wave. |
C. Sawtooth wave.
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What is the term used to identify an AC voltage that would cause the same heating in a resistor as a corresponding value of DC voltage?
A. Cosine voltage. B. Power factor. C. Root mean square (RMS). D. Average voltage. |
C. Root mean square (RMS).
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What happens to reactive power in a circuit that has both inductors and capacitors?
A. It is dissipated as heat in the circuit. B. It alternates between magnetic and electric fields and is not dissipated. C. It is dissipated as inductive and capacitive fields. D. It is dissipated as kinetic energy within the circuit. |
B. It alternates between magnetic and electric fields and is not dissipated.
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Halving the cross-sectional area of a conductor will:
A. Not affect the resistance. B. Quarter the resistance. C. Double the resistance. D. Halve the resistance. |
C. Double the resistance.
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Which of the following groups is correct for listing common materials in order of descending conductivity?
A. Silver, copper, aluminum, iron, and lead. B. Lead, iron, silver, aluminum, and copper. C. Iron, silver, aluminum, copper, and silver. D. Silver, aluminum, iron, lead, and copper. |
A. Silver, copper, aluminum, iron, and lead.
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How do you compute true power (power dissipated in the circuit) in a circuit where AC voltage and current are out of phase?
A. Multiply RMS voltage times RMS current. B. Subtract apparent power from the power factor. C. Divide apparent power by the power factor. D. Multiply apparent power times the power factor. |
D. Multiply apparent power times the power factor.
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Assuming a power source to have a fixed value of internal resistance, maximum power will be transferred to the load when:
A. The load impedance is greater than the source impedance. B. The load impedance equals the internal impedance of the source. C. The load impedance is less than the source impedance. D. The fixed values of internal impedance are not relative to the power source. |
B. The load impedance equals the internal impedance of the source.
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What value of series resistor would be needed to obtain a full scale deflection on a 50 microamp DC meter with an applied voltage of 200 volts DC?
A. 4 megohms. B. 2 megohms. C. 400 kilohms. D. 200 kilohms. |
A. 4 megohms.
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Which of the following Ohms Law formulas is incorrect?
A. I = E / R B. I = R / E C. E = I x R D. R = E / I |
B. I = R / E
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If a current of 2 amperes flows through a 50-ohm resistor, what is the voltage across the resistor?
A. 25 volts. B. 52 volts. C. 200 volts. D. 100 volts. |
D. 100 volts.
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If a 100-ohm resistor is connected across 200 volts, what is the current through the resistor?
A. 2 amperes. B. 1 ampere. C. 300 amperes. D. 20,000 amperes. |
A. 2 amperes.
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If a current of 3 amperes flows through a resistor connected to 90 volts, what is the resistance?
A. 3 ohms. B. 30 ohms. C. 93 ohms. D. 270 ohms. |
B. 30 ohms.
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A relay coil has 500 ohms resistance, and operates on 125 mA. What value of resistance should be connected in series with it to operate from 110 V DC?
A. 150 ohms. B. 220 ohms. C. 380 ohms. D. 470 ohms. |
C. 380 ohms.
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What is the peak-to-peak RF voltage on the 50 ohm output of a 100 watt transmitter?
A. 70 volts. C. 140 volts. B. 100 volts. D. 200 volts. |
D. 200 volts.
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What is the maximum DC or RMS voltage that may be connected across a 20 watt, 2000 ohm resistor?
A. 10 volts. C. 200 volts. B. 100 volts. D. 10,000 volts. |
C. 200 volts.
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A 500-ohm, 2-watt resistor and a 1500-ohm, 1-watt resistor are connected in parallel. What is the maximum voltage that can be applied across the parallel circuit without exceeding wattage ratings?
A. 22.4 volts. C. 38.7 volts. B. 31.6 volts. D. 875 volts. |
B. 31.6 volts.
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What is the most the actual transmit frequency could differ from a reading of 462,100,000 Hertz on a frequency counter with a time base accuracy of ± 0.1 ppm?
A. 46.21 Hz. B. 0.1 MHz. C. 462.1 Hz. D. 0.2 MHz. |
A. 46.21 Hz.
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The second harmonic of a 380 kHz frequency is:
A. 2 MHz. B. 760 kHz. C. 190 kHz. D. 144.4 GHz. |
B. 760 kHz.
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What is the second harmonic of SSB frequency 4146 kHz?
A. 8292 kHz. B. 4.146 MHz. C. 2073 kHz. D. 12438 kHz. |
A. 8292 kHz.
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What is the most the actual transmitter frequency could differ from a reading of 156,520,000 hertz on a frequency counter with a time base accuracy of ± 1.0 ppm?
A. 165.2 Hz. B. 15.652 kHz. C. 156.52 Hz. D. 1.4652 MHz. |
C. 156.52 Hz.
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What is the most the actual transmitter frequency could differ from a reading of 156,520,000 Hertz on a frequency counter with a time base accuracy of +/- 10 ppm?
A. 146.52 Hz. B. 1565.20 Hz. C. 10 Hz. D. 156.52 kHz. |
B. 1565.20 Hz.
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What is the most the actual transmitter frequency could differ from a reading of 462,100,000 hertz on a frequency counter with a time base accuracy of ± 1.0 ppm?
A. 46.21 MHz. B. 10 Hz. C. 1.0 MHz. D. 462.1 Hz. |
D. 462.1 Hz.
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At pi/3 radians, what is the amplitude of a sine-wave having a peak value of 5 volts?
A. -4.3 volts. C. +2.5 volts. B. -2.5 volts. D. +4.3 volts. |
D. +4.3 volts.
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At 150 degrees, what is the amplitude of a sine-wave having a peak value of 5 volts?
A. -4.3 volts. C. +2.5 volts. B. -2.5 volts. D. +4.3 volts. |
C. +2.5 volts
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At 240 degrees, what is the amplitude of a sine-wave having a peak value of 5 volts?
A. -4.3 volts. C. +2.5 volts. B. -2.5 volts. D. +4.3 volts. |
A. -4.3 volts.
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What is the equivalent to the root-mean-square value of an AC voltage?
A. AC voltage is the square root of the average AC value. B. The DC voltage causing the same heating in a given resistor at the peak AC voltage. C. The AC voltage found by taking the square of the average value of the peak AC voltage. D. The DC voltage causing the same heating in a given resistor as the RMS AC voltage of the same value. |
D. The DC voltage causing the same heating in a given resistor as the RMS AC voltage of the same value.
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What is the RMS value of a 340-volt peak-to-peak pure sine wave?
A. 170 volts AC. C. 120 volts AC. B. 240 volts AC. D. 350 volts AC. |
C. 120 volts AC.
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What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the supply voltage?
A. An exponential rate of one. B. One time constant. C. One exponential period. D. A time factor of one. |
B. One time constant.
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What is the meaning of the term “time constant of an RC circuit”? The time required to charge the capacitor in the circuit to:
A. 23.7% of the supply voltage. B. 36.8% of the supply voltage. C. 57.3% of the supply voltage. D. 63.2% of the supply voltage. |
D. 63.2% of the supply voltage.
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What is the term for the time required for the current in an RL circuit to build up to 63.2% of the maximum value?
A. One time constant. B. An exponential period of one. C. A time factor of one. D. One exponential rate. |
A. One time constant.
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What is the meaning of the term “time constant of an RL circuit”? The time required for the:
A. Current in the circuit to build up to 36.8% of the maximum value. B. Voltage in the circuit to build up to 63.2% of the maximum value. C. Current in the circuit to build up to 63.2% of the maximum value. D. Voltage in the circuit to build up to 36.8% of the maximum value. |
C. Current in the circuit to build up to 63.2% of the maximum value.
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After two time constants, the capacitor in an RC circuit is charged to what percentage of the supply voltage?
A. 36.8 % B. 63.2 % C. 86.5 % D. 95 % |
C. 86.5 %
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After two time constants, the capacitor in an RC circuit is discharged to what percentage of the starting voltage?
A. 86.5 % B. 13.5 % C. 63.2 % D. 36.8 % |
B. 13.5 %
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What is the time constant of a circuit having two 220-microfarad capacitors and two 1-megohm resistors all in parallel?
A. 22 seconds. B. 44 seconds. C. 440 seconds. D. 220 seconds. |
D. 220 seconds.
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What is the time constant of a circuit having two 100-microfarad capacitors and two 470-kilohm resistors all in series?
A. 470 seconds. B. 47 seconds. C. 4.7 seconds. D. 0.47 seconds. |
B. 47 seconds.
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What is the time constant of a circuit having a 100-microfarad capacitor and a 470-kilohm resistor in series?
A. 4700 seconds. B. 470 seconds. C. 47 seconds. D. 0.47 seconds. |
C. 47 seconds.
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What is the time constant of a circuit having a 220-microfarad capacitor and a 1-megohm resistor in parallel?
A. 220 seconds. B. 22 seconds. C. 2.2 seconds. D. 0.22 seconds. |
A. 220 seconds.
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What is the time constant of a circuit having two 100-microfarad capacitors and two 470-kilohm resistors all in parallel?
A. 470 seconds. B. 47 seconds. C. 4.7 seconds. D. 0.47 seconds. |
B. 47 seconds.
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What is the time constant of a circuit having two 220-microfarad capacitors and two 1-megohm resistors all in series?
A. 220 seconds. B. 55 seconds. C. 110 seconds. D. 440 seconds. |
A. 220 seconds.
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What is the impedance of a network composed of a 0.1-microhenry inductor in series with a 20-ohm resistor, at 30 MHz? Specify your answer in rectangular coordinates.
A. 20 -j19 B. 19 +j20 C. 20 +j19 D. 19 -j20 |
C. 20 +j19
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In rectangular coordinates, what is the impedance of a network composed of a 0.1-microhenry inductor in series with a 30-ohm resistor, at 5 MHz?
A. 30 -j3 B. 3 +j30 C. 3 -j30 D. 30 +j3 |
D. 30 +j3
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In rectangular coordinates, what is the impedance of a network composed of a 10-microhenry inductor in series with a 40-ohm resistor, at 500 MHz?
A. 40 +j31400 B. 40 -j31400 C. 31400 +j40 D. 31400 -j40 |
A. 40 +j31400
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In rectangular coordinates, what is the impedance of a network composed of a 1.0-millihenry inductor in series with a 200-ohm resistor, at 30 kHz?
A. 200 - j188 B. 200 + j188 C. 188 + j200 D. 188 - j200 |
B. 200 + j188
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In rectangular coordinates, what is the impedance of a network composed of a 0.01-microfarad capacitor in parallel with a 300-ohm resistor, at 50 kHz?
A. 150 - j159 B. 150 + j159 C. 159 - j150 D. 159 + j150 |
C. 159 - j150
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In rectangular coordinates, what is the impedance of a network composed of a 0.001-microfarad capacitor in series with a 400-ohm resistor, at 500 kHz?
A. 318 - j400 B. 400 + j318 C. 318 + j400 D. 400 - j318 |
D. 400 - j318
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What is the impedance of a network composed of a 100-picofarad capacitor in parallel with a 4000-ohm resistor, at 500 KHz? Specify your answer in polar coordinates.
A. 2490 ohms, /51.5 degrees B. 4000 ohms, /38.5 degrees C. 5112 ohms, /-38.5 degrees D. 2490 ohms, /-51.5 degrees |
D. 2490 ohms, /-51.5 degrees
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In polar coordinates, what is the impedance of a network composed of a 100-ohm-reactance inductor in series with a 100-ohm resistor?
A. 121 ohms, /35 degrees B. 141 ohms, /45 degrees C. 161 ohms, /55 degrees D. 181 ohms, /65 degrees |
B. 141 ohms, /45 degrees
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In polar coordinates, what is the impedance of a network composed of a 400-ohm-reactance capacitor in series with a 300-ohm resistor?
A. 240 ohms, /36.9 degrees B. 240 ohms, /-36.9 degrees C. 500 ohms, /-53.1 degrees D. 500 ohms, /53.1 degrees |
C. 500 ohms, /-53.1 degrees
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In polar coordinates, what is the impedance of a network composed of a 300-ohm-reactance capacitor, a 600-ohm-reactance inductor, and a 400-ohm resistor, all connected in series?
A. 500 ohms, /37 degrees B. 400 ohms, /27 degrees C. 300 ohms, /17 degrees D. 200 ohms, /10 degrees |
A. 500 ohms, /37 degrees
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In polar coordinates, what is the impedance of a network comprised of a 400-ohm-reactance inductor in parallel with a 300-ohm resistor?
A. 240 ohms, /-36.9 degrees B. 240 ohms, /36.9 degrees C. 500 ohms, /53.1 degrees D. 500 ohms, /-53.1 degrees |
B. 240 ohms, /36.9 degrees
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Using the polar coordinate system, what visual representation would you get of a voltage in a sinewave circuit?
A. To show the reactance which is present. B. To graphically represent the AC and DC component. C. To display the data on an XY chart. D. The plot shows the magnitude and phase angle. |
D. The plot shows the magnitude and phase angle.
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What is the magnitude of the impedance of a series AC circuit having a resistance of 6 ohms, an inductive reactance of 17 ohms, and zero capacitive reactance?
A. 6.6 ohms. B. 11 ohms. C. 18 ohms. D. 23 ohms. |
C. 18 ohms.
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A 1-watt, 10-volt Zener diode with the following characteristics: Imin. = 5 mA; Imax. = 95 mA; and Z = 8 ohms, is to be used as part of a voltage regulator in a 20-V power supply. Approximately what size current-limiting resistor would be used to set its bias to the midpoint of its operating range?
A. 100 ohms. B. 200 ohms. C. 1 kilohms. D. 2 kilohms. |
B. 200 ohms.
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Given a power supply with a no load voltage of 12 volts and a full load voltage of 10 volts, what is the percentage of voltage regulation?
A. 17 % B. 80 % C. 20 % D. 83 % |
C. 20 %
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What turns ratio does a transformer need in order to match a source impedance of 500 ohms to a load of 10 ohms?
A. 7.1 to 1. B. 14.2 to 1. C. 50 to 1. D. None of these. |
A. 7.1 to 1.
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Given a power supply with a full load voltage of 200 volts and a regulation of 25%, what is the no load voltage?
A. 150 volts. B. 160 volts. C. 240 volts. D. 250 volts. |
D. 250 volts.
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What is the conductance (G) of a circuit if 6 amperes of current flows when 12 volts DC is applied?
A. 0.25 Siemens (mhos). B. 0.50 Siemens (mhos). C. 1.00 Siemens (mhos). D. 1.25 Siemens (mhos). |
B. 0.50 Siemens (mhos).
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What is the magnitude of the impedance of a series AC circuit having a resistance of 6 ohms, an inductive reactance of 17 ohms, and zero capacitive reactance?
A. 6.6 ohms. B. 11 ohms. C. 18 ohms. D. 23 ohms. |
C. 18 ohms.
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A 1-watt, 10-volt Zener diode with the following characteristics: Imin. = 5 mA; Imax. = 95 mA; and Z = 8 ohms, is to be used as part of a voltage regulator in a 20-V power supply. Approximately what size current-limiting resistor would be used to set its bias to the midpoint of its operating range?
A. 100 ohms. B. 200 ohms. C. 1 kilohms. D. 2 kilohms. |
B. 200 ohms.
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Given a power supply with a no load voltage of 12 volts and a full load voltage of 10 volts, what is the percentage of voltage regulation?
A. 17 % B. 80 % C. 20 % D. 83 % |
C. 20 %
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What turns ratio does a transformer need in order to match a source impedance of 500 ohms to a load of 10 ohms?
A. 7.1 to 1. B. 14.2 to 1. C. 50 to 1. D. None of these. |
A. 7.1 to 1.
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Given a power supply with a full load voltage of 200 volts and a regulation of 25%, what is the no load voltage?
A. 150 volts. B. 160 volts. C. 240 volts. D. 250 volts. |
D. 250 volts.
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What is the conductance (G) of a circuit if 6 amperes of current flows when 12 volts DC is applied?
A. 0.25 Siemens (mhos). B. 0.50 Siemens (mhos). C. 1.00 Siemens (mhos). D. 1.25 Siemens (mhos). |
B. 0.50 Siemens (mhos).
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What happens to the conductivity of photoconductive material when light shines on it?
A. It increases. B. It decreases. C. It stays the same. D. It becomes temperature dependent. |
A. It increases.
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What is the photoconductive effect?
A. The conversion of photon energy to electromotive energy. B. The increased conductivity of an illuminated semiconductor junction. C. The conversion of electromotive energy to photon energy. D. The decreased conductivity of an illuminated semiconductor junction. |
B. The increased conductivity of an illuminated semiconductor junction.
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What does the photoconductive effect in crystalline solids produce a noticeable change in?
A. The capacitance of the solid. B. The inductance of the solid. C. The specific gravity of the solid. D. The resistance of the solid. |
D. The resistance of the solid.
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What is the description of an optoisolator?
A. An LED and a photosensitive device. B. A P-N junction that develops an excess positive charge when exposed to light. C. An LED and a capacitor. D. An LED and a lithium battery cell. |
A. An LED and a photosensitive device.
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What happens to the conductivity of a photosensitive semiconductor junction when it is illuminated?
A. The junction resistance is unchanged. B. The junction resistance decreases. C. The junction resistance becomes temperature dependent. D. The junction resistance increases |
B. The junction resistance decreases.
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What is the description of an optocoupler?
A. A resistor and a capacitor. B. Two light sources modulated onto a mirrored surface. C, An LED and a photosensitive device. D. An amplitude modulated beam encoder. |
C, An LED and a photosensitive device.
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What happens to the conductivity of photoconductive material when light shines on it?
A. It increases. B. It decreases. C. It stays the same. D. It becomes temperature dependent. |
A. It increases.
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What is the photoconductive effect?
A. The conversion of photon energy to electromotive energy. B. The increased conductivity of an illuminated semiconductor junction. C. The conversion of electromotive energy to photon energy. D. The decreased conductivity of an illuminated semiconductor junction. |
B. The increased conductivity of an illuminated semiconductor junction.
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What does the photoconductive effect in crystalline solids produce a noticeable change in?
A. The capacitance of the solid. B. The inductance of the solid. C. The specific gravity of the solid. D. The resistance of the solid. |
D. The resistance of the solid.
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What is the description of an optoisolator?
A. An LED and a photosensitive device. B. A P-N junction that develops an excess positive charge when exposed to light. C. An LED and a capacitor. D. An LED and a lithium battery cell. |
A. An LED and a photosensitive device.
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What happens to the conductivity of a photosensitive semiconductor junction when it is illuminated?
A. The junction resistance is unchanged. B. The junction resistance decreases. C. The junction resistance becomes temperature dependent. D. The junction resistance increases |
B. The junction resistance decreases.
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What is the description of an optocoupler?
A. A resistor and a capacitor. B. Two light sources modulated onto a mirrored surface. C, An LED and a photosensitive device. D. An amplitude modulated beam encoder. |
C, An LED and a photosensitive device.
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