21. When operating above its resonant frequency, a parallel RLC circuit has the characteristics of a:

A. parallel RL circuit

B. parallel RC circuit

C. parallel RLC circuit operated above its resonant frequency

D. purely resistive circuit

E. None of the above

22. Doubling the operating frequency of an inductive circuit:

A. has no effect on the inductive reactance

B. doubles the amount of inductive reactance

C. multiplies the inductive reactance by 6.28

D. cuts the inductive reactance in half

E. None of the above

23. A circuit has a Norton current of 10 mA and a Norton resistance of 10 kW. What is the Thevenin circuit?

A. 1000 V and a series resistance of 10 k Ohm

B. 100 V and a parallel resistance of 10 k Ohm

C. 100 V and a series resistance of 10 k Ohm

D. 1000 V and a parallel resistance of 10 kOhm

E. None of the above

24. Which one of the following statements is true?

A. Power dissipation of a pure capacitor increases with operating frequency

B. Power dissipation of a pure capacitor decreases with operating frequency

C. There is no meaningful relationship between the power dissipation of a pure capacitor and its operating frequency

D. All of the above

E. None of the above

25. A power transformer steps 100 V down to 10 V. If the current in its primary winding is 2 A, what is the current in the secondary winding?

A. 50 A

B. 12 A

C. 5 A

D. 20 A

E. None of the above