NSCA - AC Circuits 1

40 Questions

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Circuit Quizzes & Trivia

NSCA - AC Circuits 1


Questions and Answers
  • 1. 
    • A. 

      10 Hz

    • B. 

      5 Hz

    • C. 

      500 hz

    • D. 

      .5 Hz

    • E. 

      .1 Hz

  • 2. 
    Inductive reactance is measured in what ?
    • A. 

      Impedance

    • B. 

      Z

    • C. 

      Series

    • D. 

      Parallel

    • E. 

      Ohms

  • 3. 
    RMS power is ?
    • A. 

      Average power

    • B. 

      True power

    • C. 

      Apparent power

    • D. 

      Distributed power

    • E. 

      Peak to Peak power

  • 4. 
    How does DC react to a capacitor ?
    • A. 

      Voltage leads

    • B. 

      Capacitance rises

    • C. 

      It is blocked

    • D. 

      Phase shift

    • E. 

      Leakage

  • 5. 
    How many alternations form a cycle ?
    • A. 

      1

    • B. 

      2

    • C. 

      3

    • D. 

      4

    • E. 

      6

  • 6. 
    Inductors in series are the same as ?
    • A. 

      Resistors parallel

    • B. 

      Capacitors is series

    • C. 

      Overall impedance

    • D. 

      Resistors in series

    • E. 

      Lambda

  • 7. 
    What is the wavelength of a waveform ?(Multiple)
    • A. 

      The times per second a waveform repeats

    • B. 

      Time for a waveform to complete one cycle

    • C. 

      Used to average a waveform

    • D. 

      The distance traveled by a waveform during one second

    • E. 

      The Lambda of a waveform

  • 8. 
    The portion of the apparent power caused by inductors and capacitors ?
    • A. 

      Average power

    • B. 

      Apparent power

    • C. 

      Reactive power

    • D. 

      True power

    • E. 

      The power factor

  • 9. 
    In a capacitance circuit what is the relationship of voltage and current ?
    • A. 

      Current leads voltage

    • B. 

      There is a phase shift

    • C. 

      Voltage leads current

    • D. 

      They are in phase

    • E. 

      Reactance is created

  • 10. 
    In an AC circuit with only resistance the current is ?
    • A. 

      Always in phase with the voltage

    • B. 

      180 out of phase with voltage

    • C. 

      Leads the voltage by 180 degrees

    • D. 

      Lags behind the voltage by 180 degrees

    • E. 

      Peaked out

  • 11. 
    In a capacitive circuit the charge and discharge current must ?
    • A. 

      Be simultaneous

    • B. 

      Be in one direction

    • C. 

      Always be in different directions

    • D. 

      Always be out of phase

    • E. 

      Be in phase

  • 12. 
    A Farad is a measurement of what ?
    • A. 

      Inductance

    • B. 

      Capacitance

    • C. 

      Reactance

    • D. 

      Resistance

    • E. 

      Impedance

  • 13. 
    The characteristic of an electrical circuit to oppose the change of current flow.
    • A. 

      Resistance

    • B. 

      Capacitance

    • C. 

      Inductance

    • D. 

      Impedance

    • E. 

      Reactance

  • 14. 
    Unlike a resistor there is no power dissipation in an ideal ?
    • A. 

      Inductor

    • B. 

      Circuit

    • C. 

      Capacitor

    • D. 

      Capacitance circuit

    • E. 

      Dielectric

  • 15. 
    • A. 

      Resitance

    • B. 

      Capacitance

    • C. 

      Impedance

    • D. 

      Reactance

    • E. 

      Impedance

  • 16. 
    What is the formula for capacitance reactance ?
    • A. 

      XC = f x c

    • B. 

      XC = 6.28 x f x t

    • C. 

      XC = 1 / 6.28 x f x c

    • D. 

      XC = 6.28 x f x c

    • E. 

      XC = Square root (XC squared + X squared)

  • 17. 
    What is the period of a waveform with a frequency of 60hz ?
    • A. 

      17 milliseconds

    • B. 

      1.7 milliseconds

    • C. 

      170 milliseconds

    • D. 

      .17 seconds

    • E. 

      1.7 seconds

  • 18. 
    Capacitors in series are the same as ?
    • A. 

      Inductors in parallel

    • B. 

      Resistors in series

    • C. 

      Total impedance

    • D. 

      Reactance

    • E. 

      Capacitance reactance

  • 19. 
    Commercial power is always given in ?
    • A. 

      Peak to Peak

    • B. 

      Peak

    • C. 

      Average

    • D. 

      RMS

    • E. 

      Periodic

  • 20. 
    The power factor is relationship between what to figures ?
    • A. 

      Average and true power

    • B. 

      Reactance and average power

    • C. 

      True and apparent power

    • D. 

      Apparent and reactance power

    • E. 

      Resistance and reactance

  • 21. 
    In an inductive circuit what happens when frequency increases ?
    • A. 

      No change

    • B. 

      There is a reduction in inductance

    • C. 

      There is an increase in inductance

    • D. 

      There is an increase in inductive reactance

    • E. 

      There is a decrease in inductive reactance

  • 22. 
    What is the formula to find RMS voltage ?
    • A. 

      RMS = Peak / .707

    • B. 

      RMS = .707 x Peak

    • C. 

      RMS = .637 x Peak

    • D. 

      RMS = .077 x Peak

    • E. 

      RMS = .7 X Peak

  • 23. 
    On a current transformer which set of windings always has more turns ?
    • A. 

      They are the same

    • B. 

      The primary

    • C. 

      The like-wound side

    • D. 

      The secondary

    • E. 

      The unlike-wound side

  • 24. 
    How is a current transformer connected ?
    • A. 

      In series

    • B. 

      In parallel

    • C. 

      In proximity

    • D. 

      Across the differing phases

    • E. 

      Wrapped

  • 25. 
    The product of the source voltage and total current ?
    • A. 

      Average power

    • B. 

      Apparent power

    • C. 

      Reactive power

    • D. 

      True power

    • E. 

      The power factor

  • 26. 
    In an inductive circuit what is the relationship of voltage and current ?
    • A. 

      Current leads voltage

    • B. 

      There is a phase shift

    • C. 

      Voltage leads current

    • D. 

      They are in phase

    • E. 

      Reactance is created

  • 27. 
    A transformer 400 turns on the primary and 100 turns on the secondary ?
    • A. 

      Step up 4:1

    • B. 

      Step up 1:4

    • C. 

      Step down 1:4

    • D. 

      Step down 4:1

    • E. 

      Step up 1:5

  • 28. 
    The power consumed by resistance is ?
    • A. 

      Average power

    • B. 

      Apparent power

    • C. 

      Reactive power

    • D. 

      True power

    • E. 

      The power factor

  • 29. 
    True power is the product of resistance and ?
    • A. 

      Voltage

    • B. 

      Current squared

    • C. 

      Reactance

    • D. 

      Current

    • E. 

      Voltage squared

  • 30. 
    The period of a waveform is the inverse of what ?
    • A. 

      Cycle

    • B. 

      Peak

    • C. 

      Frequency

    • D. 

      Time

    • E. 

      Hz

  • 31. 
    What is resonance ?
    • A. 

      Total impedance

    • B. 

      Increase in capacitance reactance

    • C. 

      Increase in inductive reactance

    • D. 

      Impedance is equal to resistance

    • E. 

      Inductive reactance is equal to capacitance reactance

  • 32. 
    What is the formula for inductive reactance ?
    • A. 

      XL = f x L

    • B. 

      XL = 6.28 x f x t

    • C. 

      XL = 1 / 6.28 x f x l

    • D. 

      XL = 6.28 x f x l

    • E. 

      XL = Square root (XL squared + X squared)

  • 33. 
    Total capacitance of a two 40 microfarad capacitors
    • A. 

      10

    • B. 

      40

    • C. 

      80

    • D. 

      20

    • E. 

      5

  • 34. 
    At resonance what happens to resistance ?
    • A. 

      Nothing

    • B. 

      It decrease

    • C. 

      Capacitance cancels out resistance

    • D. 

      It increases

    • E. 

      All the above

  • 35. 
    In a transformer how is the frequency when crossing the coils ?
    • A. 

      Change in magnitude

    • B. 

      Increases

    • C. 

      Decreases

    • D. 

      Stays the same

    • E. 

      Reduces in magnitude

  • 36. 
    What is the peek voltage of a 120Vac circuit ?
    • A. 

      117 volts

    • B. 

      120 volts

    • C. 

      150 volts

    • D. 

      170 volts

    • E. 

      110 volts

  • 37. 
    What is the formula to find the average voltage ?
    • A. 

      Average = .707 x Peak

    • B. 

      Average = RMS / .707

    • C. 

      Average = .673 x Peak

    • D. 

      Average = Peak x .637

    • E. 

      Average = Peak x .077

  • 38. 
    Total opposition of current flow in a circuit ?
    • A. 

      Capacitance reactance

    • B. 

      Impedance

    • C. 

      Inductive reactance

    • D. 

      Resistance

    • E. 

      Resistive reactance

  • 39. 
    A transformer in which the primary and secondary voltages are out of phase ?
    • A. 

      Current transformer

    • B. 

      Autotransformer

    • C. 

      Like-wound

    • D. 

      Dotted

    • E. 

      Unlike-wound

  • 40. 
    Total inductive reactance of a 25 henry inductor in a 60 Hz circuit ?
    • A. 

      2132 ohms

    • B. 

      1.06 ohms

    • C. 

      5652 ohms

    • D. 

      9420 ohms

    • E. 

      6536 ohms