Questions Without Answers For Alternating Current

Question File Number 8



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  • An 'alternating current' is so called because:
    • it reverses direction periodically
    • it travels through a circuit using alternate paths
    • its direction of travel is uncertain
    • its direction of travel can be altered by a switch
    • ==========================
  • The time for one cycle of a 100 Hz signal is:
    • 1 second
    • 0.01 second
    • 0.0001 second
    • 10 seconds
    • ==========================
  • A 50 hertz current in a wire means that:
    • a potential difference of 50 volts exists across the wire
    • the current flowing in the wire is 50 amperes
    • the power dissipated in the wire is 50 watts
    • a cycle is completed 50 times in each second
    • ==========================
  • The current in an AC circuit completes a cycle in 0.1 second. So the frequency is:
    • 1 Hz
    • 10 Hz
    • 100 Hz
    • 1000 Hz
    • ==========================
  • An impure signal is found to have 2 kHz and 4 kHz components. This 4 kHz signal is:
    • a fundamental of the 2 kHz signal
    • a sub-harmonic of 2 kHz
    • the DC component of the main signal
    • a harmonic of the 2 kHz signal
    • ==========================
  • The correct name for the equivalent of 'one cycle per second' is one:
    • henry
    • volt
    • hertz
    • coulomb
    • ==========================
  • One megahertz is equal to:
    • 0.0001 Hz
    • 100 kHz
    • 1000 kHz
    • 10 Hz
    • ==========================
  • One GHz is equal to:
    • 1000 kHz
    • 10 MHz
    • 100 MHz
    • 1000 MHz
    • ==========================
  • The 'rms value' of a sine-wave signal is:
    • half the peak voltage
    • 1.414 times the peak voltage
    • the peak-to-peak voltage
    • 0.707 times the peak voltage
    • ==========================
  • A sine-wave alternating current of 10 ampere peak has an rms value of:
    • 5 amp
    • 7.07 amp
    • 14.14 amp
    • 20 amp
    • ==========================

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Compiled Wed Jun 30 2010 at 4:20:20pm


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