Principles

Key Topic 1:  Electrical Elements

3-1A1 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.

Principles

Key Topic 1:  Electrical Elements

3-1A2 What is the basic unit of electrical power?

A. Ohm.

B. Watt.

C. Volt.

D. Ampere.

B. Watt.

Principles

Key Topic 1:  Electrical Elements

3-1A3 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.

Principles

Key Topic 1:  Electrical Elements

3-1A4 What device is used to store electrical energy in an electrostatic field?

A. Battery.

B. Transformer.

C. Capacitor.

D. Inductor.

C. Capacitor.

Principles

Key Topic 1:  Electrical Elements

3-1A5 What formula would determine the inductive reactance of a coil if frequency and coil inductance are known?

A. XL = ∏f L

B. XL = 2∏f L

C. XL = 1 / 2∏f C

D. XL = 1 / R2+X2

B. XL = 2∏f L

Principles

Key Topic 1:  Electrical Elements

3-1A6 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.

Principles

Key Topic 2:  Magnetism

3-2A1 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.

Principles

Key Topic 2:  Magnetism

3-2A2 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.

Principles

Key Topic 2:  Magnetism

3-2A3 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.

Principles

Key Topic 2:  Magnetism

3-2A4 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.

Principles

Key Topic 2:  Magnetism

3-2A5 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.

Principles

Key Topic 2:  Magnetism

3-2A6 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.

Principles

Key Topic 3: Materials

3-3A1 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.

Principles

Key Topic 3: Materials

3-3A2 What is the relative dielectric constant for air?

A. 1

B. 2

C. 4

D. 0

A. 1

Principles

Key Topic 3: Materials

3-3A3 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.

Principles

Key Topic 3: Materials

3-3A4 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.

Principles

Key Topic 3: Materials

3-3A5 Corrosion resulting from electric current flow between dissimilar metals is called:

A. Electrolysis.

B. Stray current corrosion.

C. Oxygen starvation corrosion.

D. Galvanic corrosion.

Principles

Key Topic 3: Materials

3-3A6 Which of these will be most useful for insulation at UHF frequencies?

A. Rubber.

B. Mica.

C. Wax impregnated paper.

D. Lead.

B. Mica.

Principles

Key Topic 4:  Resistance, Capacitance & Inductance

3-4A1 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

Principles

Key Topic 4:  Resistance, Capacitance & Inductance

3-4A2 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.

Principles

Key Topic 4:  Resistance, Capacitance & Inductance

3-4A3 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.

Principles

Key Topic 4:  Resistance, Capacitance & Inductance

3-4A4 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.

Principles

Key Topic 4:  Resistance, Capacitance & Inductance

3-4A5 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.

Principles

Key Topic 4:  Resistance, Capacitance & Inductance

3-4A6 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.

Principles

Key Topic 5:  Semi-conductors

3-5A1 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).

Principles

Key Topic 5:  Semi-conductors

3-5A2 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.

Principles

Key Topic 5:  Semi-conductors

3-5A3 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.

Principles

Key Topic 5:  Semi-conductors

3-5A4 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.

Principles

Key Topic 5:  Semi-conductors

3-5A5 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.

Principles

Key Topic 5:  Semi-conductors

3-5A6 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.

Principles

Key Topic 6:  Electrical Measurements

3-6A1 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.

Principles

Key Topic 6:  Electrical Measurements

3-6A2 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

Principles

Key Topic 6:  Electrical Measurements

3-6A3 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.

Principles

Key Topic 6:  Electrical Measurements

3-6A4 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.

Principles

Key Topic 6:  Electrical Measurements

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?

A. 0.707

B. 1.414

C. 0.9

D. 3.14

Principles

Key Topic 6:  Electrical Measurements

3-6A6 What is the peak voltage at a common household electrical outlet?

A. 234 volts.

B. 117 volts.

C. 331 volts.

D. 165.5 volts.

Principles

Key Topic 7:  Waveforms

3-7A1 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.

Principles

Key Topic 7:  Waveforms

3-7A2 How many degrees are there in one complete sine wave cycle?

A. 90 degrees.

B. 270 degrees.

C. 180 degrees.

D. 360 degrees.

Principles

Key Topic 7:  Waveforms

3-7A3 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.

Principles

Key Topic 7:  Waveforms

3-7A4 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.

Principles

Key Topic 7:  Waveforms

3-7A5 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.

Principles

Key Topic 7:  Waveforms

3-7A6 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.

Principles

Key Topic 8:  Conduction

3-8A1 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.

Principles

Key Topic 8:  Conduction

3-8A2 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.

Principles

Key Topic 8:  Conduction

3-8A3 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

Principles

Key Topic 8:  Conduction

3-8A4 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.

Principles

Key Topic 8:  Conduction

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?

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.

Principles

Key Topic 8:  Conduction

3-8A6 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.