ANSWERS TO QUESTIONS Q1. THROUGH Q31.
A1. An inductor opposes a change in current.
A2. Current lags voltage by 90 (ELI).
A3. Inductive reactance.
A4. XL = 2pfL.
A5. XL increases.
A6. XL decreases.
A7. The capacitor opposes any change in voltage.
A8. Current leads voltage by 90 (ICE).
A9. Capacitive reactance.
A10.
A11. XC increases.
A12. XC decreases.
A13. X = XL - XC or X = XC - XL
A14. 30 W
(capacitive).
A15. Impedance.
A16.
A17. Z = 5W.
A18.
A19. True power is the power dissipated in the resistance of the circuit or the power
actually used in the circuit.
A20. Watt.
A21. True Power = (IR)2R.
A22. Reactive power is the power returned to the source by the reactive components of the
circuit.
A23. var.
A24.
A25. The power that appears to the source because of circuit impedance, or the combination
of true power and reactive power.
A26. VA (volt-amperes).
A27.
A28. PF is a number representing the portion of apparent power actually dissipated in a
circuit.
A29.
A30. Add 10 ohms of capacitive reactance to the circuit.
A31. In a series circuit impedance is calculated from the values of resistance and
reactance. In a parallel circuit, the values of resistive current and reactive current
must be used to calculate total current (impedance current) and this value must be divided
into the source voltage to calculate the impedance.
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