SUBELEMENT T5 – Electrical principles: math for electronics; electronic principles; Ohm’s Law – [4 Exam Questions - 4 Groups] Flashcards
T5A01 (D)
Electrical current is measured in which of the following units?
D. Amperes
T5A02 (B)
Electrical power is measured in which of the following units?
B. Watts
T5A03 (D)
What is the name for the flow of electrons in an electric circuit?
D. Current
T5A04 (B)
What is the name for a current that flows only in one direction?
B. Direct current
T5A05 (A)
What is the electrical term for the electromotive force (EMF) that causes electron flow?
A. Voltage
T5A06 (A)
How much voltage does a mobile transceiver typically require?
A. About 12 volts
T5A07 (C)
Which of the following is a good electrical conductor?
C. Copper
T5A08 (B)
Which of the following is a good electrical insulator?
B. Glass
T5A09 (A)
What is the name for a current that reverses direction on a regular basis?
A. Alternating current
T5A10 (C)
Which term describes the rate at which electrical energy is used?
C. Power
T5A11 (A)
What is the unit of electromotive force?
A. The volt
T5A12 (D)
What describes the number of times per second that an alternating current makes a complete cycle?
D. Frequency
T5A13 (A)
In which type of circuit is current the same through all components?
A. Series
T5A14 (B)
In which type of circuit is voltage the same across all components?
B. Parallel
T5B01 (C)
How many milliamperes is 1.5 amperes?
C. 1500 milliamperes
T5B02 (A)
What is another way to specify a radio signal frequency of 1,500,000 hertz?
A. 1500 kHz
T5B03 (C)
How many volts are equal to one kilovolt?
C. One thousand volts
T5B04 (A)
How many volts are equal to one microvolt?
A. One one-millionth of a volt
T5B05 (B)
Which of the following is equal to 500 milliwatts?
B. 0.5 watts
T5B06 (C)
If an ammeter calibrated in amperes is used to measure a 3000- milliampere current, what reading would it show?
C. 3 amperes
T5B07 (C)
If a frequency display calibrated in megahertz shows a reading of 3.525 MHz, what would it show if it were calibrated in kilohertz?
C. 3525 kHz
T5B08 (B)
How many microfarads are equal to 1,000,000 picofarads?
B. 1 microfarad
T5B09 (B)
What is the approximate amount of change, measured in decibels (dB), of a power increase from 5 watts to 10 watts?
B. 3 dB
T5B10 (C)
What is the approximate amount of change, measured in decibels (dB), of a power decrease from 12 watts to 3 watts?
C. -6 dB
T5B11 (A)
What is the amount of change, measured in decibels (dB), of a power increase from 20 watts to 200 watts?
A. 10 dB
T5B12 (A)
Which of the following frequencies is equal to 28,400 kHz?
A. 28.400 MHz
T5B13 (C)
If a frequency display shows a reading of 2425 MHz, what frequency is that in GHz?
C. 2.425 GHz
T5C01 (D)
What is the ability to store energy in an electric field called?
D. Capacitance
T5C02 (A)
What is the basic unit of capacitance?
A. The farad
T5C03 (D)
What is the ability to store energy in a magnetic field called?
D. Inductance
T5C04 (C)
What is the basic unit of inductance?
C. The henry
T5C05 (A)
What is the unit of frequency?
A. Hertz
T5C06 (A)
What does the abbreviation “RF” refer to?
A. Radio frequency signals of all types
T5C07 (B)
A radio wave is made up of what type of energy?
B. Electromagnetic
T5C08 (A)
What is the formula used to calculate electrical power in a DC circuit?
A. Power (P) equals voltage (E) multiplied by current (I)
T5C09 (A)
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
T5C10 (B)
How much power is being used in a circuit when the applied voltage is 12 volts DC and the current is 2.5 amperes?
B. 30 watts
T5C11 (B)
How many amperes are flowing in a circuit when the applied voltage is 12 volts DC and the load is 120 watts?
B. 10 amperes
T5C12 (A)
What is impedance?
A. A measure of the opposition to AC current flow in a circuit
T5C13 (D)
What are the units of impedance?
D. Ohms
T5C14 (D)
What is the proper abbreviation for megahertz?
D. MHz
T5D01 (B)
What formula is used to calculate current in a circuit?
B. Current (I) equals voltage (E) divided by resistance (R)
T5D02 (A)
What formula is used to calculate voltage in a circuit?
A. Voltage (E) equals current (I) multiplied by resistance (R)
T5D03 (B)
What formula is used to calculate resistance in a circuit?
B. Resistance (R) equals voltage (E) divided by current (I)
T5D04 (B)
What is the resistance of a circuit in which a current of 3 amperes flows through a resistor connected to 90 volts?
B. 30 ohms
T5D05 (C)
What is the resistance in a circuit for which the applied voltage is 12 volts and the current flow is 1.5 amperes?
C. 8 ohms
T5D06 (A)
What is the resistance of a circuit that draws 4 amperes from a 12-volt source?
A. 3 ohms
T5D07 (D)
What is the current in a circuit with an applied voltage of 120 volts and a resistance of 80 ohms?
D. 1.5 amperes
T5D08 (C)
What is the current through a 100-ohm resistor connected across 200 volts?
C. 2 amperes
T5D09 (C)
What is the current through a 24-ohm resistor connected across 240 volts?
C. 10 amperes
T5D10 (A)
What is the voltage across a 2-ohm resistor if a current of 0.5 amperes flows through it?
A. 1 volt
T5D11 (B)
What is the voltage across a 10-ohm resistor if a current of 1 ampere flows through it?
B. 10 volts
T5D12 (D)
What is the voltage across a 10-ohm resistor if a current of 2 amperes flows through it?
D. 20 volts
T5D13 (B)
What happens to current at the junction of two components in series?
B. It is unchanged
T5D14 (A)
What happens to current at the junction of two components in parallel?
A. It divides between them dependent on the value of the components
T5D15 (C)
What is the voltage across each of two components in series with a voltage source?
C. It is determined by the type and value of the components
T5D16 (D)
What is the voltage across each of two components in parallel with a voltage source?
D. The same voltage as the source