87 lines
2.8 KiB
Markdown
87 lines
2.8 KiB
Markdown
G5B – The decibel; current and voltage dividers; electrical power calculations; sine wave root-mean-square (RMS) values; PEP calculations
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- [[G5B01]] (B)
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What dB change represents a factor of two increase or decrease in power? #card
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- A. Approximately 2 dB
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- B. Approximately 3 dB
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- C. Approximately 6 dB
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- D. Approximately 9 dB
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- [[G5B02]] (C)
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How does the total current relate to the individual currents in a circuit of parallel resistors? #card
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- A. It equals the average of the branch currents
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- B. It decreases as more parallel branches are added to the circuit
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- C. It equals the sum of the currents through each branch
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- D. It is the sum of the reciprocal of each individual voltage drop
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- [[G5B03]] (B)
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How many watts of electrical power are consumed if 400 VDC is supplied to an 800-ohm load? #card
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- A. 0.5 watts
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- B. 200 watts
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- C. 400 watts
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- D. 3200 watts
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- [[G5B04]] (A)
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How many watts of electrical power are consumed by a 12 VDC light bulb that draws 0.2 amperes? #card
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- A. 2.4 watts
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- B. 24 watts
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- C. 6 watts
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- D. 60 watts
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- [[G5B05]] (A)
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How many watts are consumed when a current of 7.0 milliamperes flows through a 1,250-ohm resistance? #card
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- A. Approximately 61 milliwatts
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- B. Approximately 61 watts
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- C. Approximately 11 milliwatts
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- D. Approximately 11 watts
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- [[G5B06]] (B)
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What is the PEP produced by 200 volts peak-to-peak across a 50-ohm dummy load? #card
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- A. 1.4 watts
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- B. 100 watts
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- C. 353.5 watts
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- D. 400 watts
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- [[G5B07]] (C)
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What value of an AC signal produces the same power dissipation in a resistor as a DC voltage of the same value? #card
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- A. The peak-to-peak value
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- B. The peak value
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- C. The RMS value
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- D. The reciprocal of the RMS value
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- [[G5B08]] (D)
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What is the peak-to-peak voltage of a sine wave with an RMS voltage of 120 volts? #card
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- A. 84.8 volts
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- B. 169.7 volts
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- C. 240.0 volts
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- D. 339.4 volts
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- [[G5B09]] (B)
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What is the RMS voltage of a sine wave with a value of 17 volts peak? #card
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- A. 8.5 volts
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- B. 12 volts
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- C. 24 volts
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- D. 34 volts
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- [[G5B10]] (C)
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What percentage of power loss is equivalent to a loss of 1 dB? #card
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- A. 10.9 percent
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- B. 12.2 percent
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- C. 20.6 percent
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- D. 25.9 percent
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- [[G5B11]] (B)
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What is the ratio of PEP to average power for an unmodulated carrier? #card
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- A. 0.707
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- B. 1.00
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- C. 1.414
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- D. 2.00
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- [[G5B12]] (B)
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What is the RMS voltage across a 50-ohm dummy load dissipating 1200 watts? #card
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- A. 173 volts
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- B. 245 volts
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- C. 346 volts
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- D. 692 volts
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- [[G5B13]] (B)
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What is the output PEP of an unmodulated carrier if the average power is 1060 watts? #card
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- A. 530 watts
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- B. 1060 watts
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- C. 1500 watts
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- D. 2120 watts
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- [[G5B14]] (B)
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What is the output PEP of 500 volts peak-to-peak across a 50-ohm load? #card
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- A. 8.75 watts
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- B. 625 watts
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- C. 2500 watts
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- D. 5000 watts
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