2025-05-01 13:59:40 -05:00

2.8 KiB
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G5B The decibel; current and voltage dividers; electrical power calculations; sine wave root-mean-square (RMS) values; PEP calculations

  • G5B01 (B) What dB change represents a factor of two increase or decrease in power? #card
    • A. Approximately 2 dB
    • B. Approximately 3 dB
    • C. Approximately 6 dB
    • D. Approximately 9 dB
  • G5B02 (C) How does the total current relate to the individual currents in a circuit of parallel resistors? #card
    • A. It equals the average of the branch currents
    • B. It decreases as more parallel branches are added to the circuit
    • C. It equals the sum of the currents through each branch
    • D. It is the sum of the reciprocal of each individual voltage drop
  • G5B03 (B) How many watts of electrical power are consumed if 400 VDC is supplied to an 800-ohm load? #card
    • A. 0.5 watts
    • B. 200 watts
    • C. 400 watts
    • D. 3200 watts
  • G5B04 (A) How many watts of electrical power are consumed by a 12 VDC light bulb that draws 0.2 amperes? #card
    • A. 2.4 watts
    • B. 24 watts
    • C. 6 watts
    • D. 60 watts
  • G5B05 (A) How many watts are consumed when a current of 7.0 milliamperes flows through a 1,250-ohm resistance? #card
    • A. Approximately 61 milliwatts
    • B. Approximately 61 watts
    • C. Approximately 11 milliwatts
    • D. Approximately 11 watts
  • G5B06 (B) What is the PEP produced by 200 volts peak-to-peak across a 50-ohm dummy load? #card
    • A. 1.4 watts
    • B. 100 watts
    • C. 353.5 watts
    • D. 400 watts
  • G5B07 (C) What value of an AC signal produces the same power dissipation in a resistor as a DC voltage of the same value? #card
    • A. The peak-to-peak value
    • B. The peak value
    • C. The RMS value
    • D. The reciprocal of the RMS value
  • G5B08 (D) What is the peak-to-peak voltage of a sine wave with an RMS voltage of 120 volts? #card
    • A. 84.8 volts
    • B. 169.7 volts
    • C. 240.0 volts
    • D. 339.4 volts
  • G5B09 (B) What is the RMS voltage of a sine wave with a value of 17 volts peak? #card
    • A. 8.5 volts
    • B. 12 volts
    • C. 24 volts
    • D. 34 volts
  • G5B10 (C) What percentage of power loss is equivalent to a loss of 1 dB? #card
    • A. 10.9 percent
    • B. 12.2 percent
    • C. 20.6 percent
    • D. 25.9 percent
  • G5B11 (B) What is the ratio of PEP to average power for an unmodulated carrier? #card
    • A. 0.707
    • B. 1.00
    • C. 1.414
    • D. 2.00
  • G5B12 (B) What is the RMS voltage across a 50-ohm dummy load dissipating 1200 watts? #card
    • A. 173 volts
    • B. 245 volts
    • C. 346 volts
    • D. 692 volts
  • G5B13 (B) What is the output PEP of an unmodulated carrier if the average power is 1060 watts? #card
    • A. 530 watts
    • B. 1060 watts
    • C. 1500 watts
    • D. 2120 watts
  • G5B14 (B) What is the output PEP of 500 volts peak-to-peak across a 50-ohm load? #card
    • A. 8.75 watts
    • B. 625 watts
    • C. 2500 watts
    • D. 5000 watts