Technician Subelement T5 Flashcards
Electrical current is measured in which of the following units?
A. Volts
B. Watts
C. Ohms
D. Amperes
Amperes
Electrical power is measured in which of the following units?
A. Volts
B. Watts
C. Ohms
D. Amperes
Watts
What is the name for the flow of electrons in an electric circuit?
A. Voltage
B. Resistance
C. Capacitance
D. Current
Current
What is the name for a current that flows only in one direction?
A. Alternating current
B. Direct current
C. Normal current
D. Smooth current
Direct current
What is the electrical term for the electromotive force (EMF) that causes electron flow?
A. Voltage
B. Ampere-hours
C. Capacitance
D. Inductance
Voltage
How much voltage does a mobile transceiver typically require?
A. About 12 volts
B. About 30 volts
C. About 120 volts
D. About 240 volts
About 12 volts
Which of the following is a good electrical conductor?
A. Glass
B. Wood
C. Copper
D. Rubber
Copper
Which of the following is a good electrical insulator?
A. Copper
B. Glass
C. Aluminum
D. Mercury
Glass
What is the name for a current that reverses direction on a regular basis?
A. Alternating current
B. Direct current
C. Circular current
D. Vertical current
Alternating current
Which term describes the rate at which electrical energy is used?
A. Resistance
B. Current
C. Power
D. Voltage
Power
What is the unit of electromotive force?
A. The volt
B. The watt
C. The ampere
D. The ohm
The volt
What describes the number of times per second that an alternating current makes a complete cycle?
A. Pulse rate
B. Speed
C. Wavelength
D. Frequency
Frequency
In which type of circuit is current the same through all components?
A. Series
B. Parallel
C. Resonant
D. Branch
Series
In which type of circuit is voltage the same across all components?
A. Series
B. Parallel
C. Resonant
D. Branch
Parallel
How many milliamperes is 1.5 amperes?
A. 15 milliamperes
B. 150 milliamperes
C. 1500 milliamperes
D. 15,000 milliamperes
1500 milliamperes
What is another way to specify a radio signal frequency of 1,500,000 hertz?
A. 1500 kHz
B. 1500 MHz
C. 15 GHz
D. 150 kHz
1500 kHz
How many volts are equal to one kilovolt?
A. One one-thousandth of a volt
B. One hundred volts
C. One thousand volts
D. One million volts
One thousand volts
How many volts are equal to one microvolt?
A. One one-millionth of a volt
B. One million volts
C. One thousand kilovolts
D. One one-thousandth of a volt
One one-millionth of a volt
Which of the following is equal to 500 milliwatts?
A. 0.02 watts
B. 0.5 watts
C. 5 watts
D. 50 watts
0.5 watts
If an ammeter calibrated in amperes is used to measure a 3000- milliampere current, what reading would it show?
A. 0.003 amperes
B. 0.3 amperes
C. 3 amperes
D. 3,000,000 amperes
3 amperes
If a frequency display calibrated in megahertz shows a reading of 3.525 MHz, what would it show if it were calibrated in kilohertz?
A. 0.003525 kHz
B. 35.25 kHz
C. 3525 kHz
D. 3,525,000 kHz
3525 kHz
How many microfarads are equal to 1,000,000 picofarads?
A. 0.001 microfarads
B. 1 microfarad
C. 1000 microfarads
D. 1,000,000,000 microfarads
1 microfarad
What is the approximate amount of change, measured in decibels (dB), of a power increase from 5 watts to 10 watts?
A. 2 dB
B. 3 dB
C. 5 dB
D. 10 dB
3 dB
What is the approximate amount of change, measured in decibels (dB), of a power decrease from 12 watts to 3 watts?
A. -1 dB
B. -3 dB
C. -6 dB
D. -9 dB
-6 dB
What is the amount of change, measured in decibels (dB), of a power increase from 20 watts to 200 watts?
A. 10 dB
B. 12 dB
C. 18 dB
D. 28 dB
10 dB
Which of the following frequencies is equal to 28,400 kHz?
A. 28.400 MHz
B. 2.800 MHz
C. 284.00 MHz
D. 28.400 kHz
28.400 MHz
If a frequency display shows a reading of 2425 MHz, what frequency is that in GHz?
A. 0.002425 GHz
B. 24.25 GHz
C. 2.425 GHz
D. 2425 GHz
2.425 GHz
What is the ability to store energy in an electric field called?
A. Inductance
B. Resistance
C. Tolerance
D. Capacitance
Capacitance
What is the basic unit of capacitance?
A. The farad
B. The ohm
C. The volt
D. The henry
The farad
What is the ability to store energy in a magnetic field called?
A. Admittance
B. Capacitance
C. Resistance
D. Inductance
Inductance
What is the basic unit of inductance?
A. The coulomb
B. The farad
C. The henry
D. The ohm
The henry
What is the unit of frequency?
A. Hertz
B. Henry
C. Farad
D. Tesla
Hertz
What does the abbreviation “RF” refer to?
A. Radio frequency signals of all types
B. The resonant frequency of a tuned circuit
C. The real frequency transmitted as opposed to the apparent frequency
D. Reflective force in antenna transmission lines
Radio frequency signals of all types
A radio wave is made up of what type of energy?
A. Pressure
B. Electromagnetic
C. Gravity
D. Thermal
Electromagnetic
What is the formula used to calculate electrical power in a DC circuit?
A. Power (P) equals voltage (E) multiplied by current (I)
B. Power (P) equals voltage (E) divided by current (I)
C. Power (P) equals voltage (E) minus current (I)
D. Power (P) equals voltage (E) plus current (I)
Power (P) equals voltage (E) multiplied by current (I)
How much power is being used in a circuit when the applied voltage is 13.8 volts DC and the current is 10 amperes?
A. 138 watts
B. 0.7 watts
C. 23.8 watts
D. 3.8 watts
138 watts
How much power is being used in a circuit when the applied voltage is 12 volts DC and the current is 2.5 amperes?
A. 4.8 watts
B. 30 watts
C. 14.5 watts
D. 0.208 watts
30 watts
How many amperes are flowing in a circuit when the applied voltage is 12 volts DC and the load is 120 watts?
A. 0.1 amperes
B. 10 amperes
C. 12 amperes
D. 132 amperes
10 amperes
What is impedance?
A. A measure of the opposition to AC current flow in a circuit
B. The inverse of resistance
C. The Q or Quality Factor of a component
D. The power handling capability of a component
A measure of the opposition to AC current flow in a circuit
What is a unit of impedance?
A. Volts
B. Amperes
C. Coulombs
D. Ohms
Ohms
What is the proper abbreviation for megahertz?
A. mHz
B. mhZ
C. Mhz
D. MHz
MHz
What formula is used to calculate current in a circuit?
A. Current (I) equals voltage (E) multiplied by resistance (R)
B. Current (I) equals voltage (E) divided by resistance (R)
C. Current (I) equals voltage (E) added to resistance (R)
D. Current (I) equals voltage (E) minus resistance (R)
Current (I) equals voltage (E) divided by resistance (R)
What formula is used to calculate voltage in a circuit?
A. Voltage (E) equals current (I) multiplied by resistance (R)
B. Voltage (E) equals current (I) divided by resistance (R)
C. Voltage (E) equals current (I) added to resistance (R)
D. Voltage (E) equals current (I) minus resistance (R)
Voltage (E) equals current (I) multiplied by resistance (R)
What formula is used to calculate resistance in a circuit?
A. Resistance (R) equals voltage (E) multiplied by current (I)
B. Resistance (R) equals voltage (E) divided by current (I)
C. Resistance (R) equals voltage (E) added to current (I)
D. Resistance (R) equals voltage (E) minus current (I)
Resistance (R) equals voltage (E) divided by current (I)
What is the resistance of a circuit in which a current of 3 amperes flows through a resistor connected to 90 volts?
A. 3 ohms
B. 30 ohms
C. 93 ohms
D. 270 ohms
30 ohms
What is the resistance in a circuit for which the applied voltage is 12 volts and the current flow is 1.5 amperes?
A. 18 ohms
B. 0.125 ohms
C. 8 ohms
D. 13.5 ohms
8 ohms
What is the resistance of a circuit that draws 4 amperes from a 12-volt source?
A. 3 ohms
B. 16 ohms
C. 48 ohms
D. 8 ohms
3 ohms
What is the current in a circuit with an applied voltage of 120 volts and a resistance of 80 ohms?
A. 9600 amperes
B. 200 amperes
C. 0.667 amperes
D. 1.5 amperes
1.5 amperes
What is the current through a 100-ohm resistor connected across 200 volts?
A. 20,000 amperes
B. 0.5 amperes
C. 2 amperes
D. 100 amperes
2 amperes
What is the current through a 24-ohm resistor connected across 240 volts?
A. 24,000 amperes
B. 0.1 amperes
C. 10 amperes
D. 216 amperes
10 amperes
What is the voltage across a 2-ohm resistor if a current of 0.5 amperes flows through it?
A. 1 volt
B. 0.25 volts
C. 2.5 volts
D. 1.5 volts
1 volt
What is the voltage across a 10-ohm resistor if a current of 1 ampere flows through it?
A. 1 volt
B. 10 volts
C. 11 volts
D. 9 volts
10 volts
What is the voltage across a 10-ohm resistor if a current of 2 amperes flows through it?
A. 8 volts
B. 0.2 volts
C. 12 volts
D. 20 volts
20 volts
What happens to current at the junction of two components in series?
A. It divides equally between them
B. It is unchanged
C. It divides based on the on the value of the components
D. The current in the second component is zero
It is unchanged
What happens to current at the junction of two components in parallel?
A. It divides between them dependent on the value of the components
B. It is the same in both components
C. Its value doubles
D. Its value is halved
It divides between them dependent on the value of the components
What is the voltage across each of two components in series with a voltage source?
A. The same voltage as the source
B. Half the source voltage
C. It is determined by the type and value of the components
D. Twice the source voltage
It is determined by the type and value of the components
What is the voltage across each of two components in parallel with a voltage source?
A. It is determined by the type and value of the components
B. Half the source voltage
C. Twice the source voltage
D. The same voltage as the source
The same voltage as the source
