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16. 

The value of a capacitor can be made larger by:
A. increasing the area of the plates
B. decreasing the area of the plates
C. increasing the frequency of the applied voltage
D. increasing the voltage applied to the plates
E. None of the above
17. 

The primary impedance of a transformer is 60 ohm and the secondary impedance is 120 ohm. What is the impedance ratio?
A. 0.25
B. 180
C. 0.5
D. 4
E. None of the above
18. 

Suppose a voltage source has an ideal voltage of 12V and an internal resistance of 0.5W. For what values of load resistance will the voltage source appear stiff?
A. 5 Ohm
B. 50 Ohm or more
C. 100 Ohm
D. 6 Ohm
E. None of the above
19. 

Electron current is flowing through a conductor in a direction you might describe as straight into this page. What is the direction of the resulting magnetic field?
A. Clockwise
B. Counterclockwise
C. Out of this page
D. Into this page
E. None of the above
20. 

Which one of the following principles best describes the basic operation of an electromagnet?
A. Current is induced in a conductor that is moving through a magnetic field
B. Like magnetic poles repel, while unlike poles attract
C. Current flowing through a conductor generates a magnetic field
D. Like magnetic poles attract, while unlike poles repel
E. None of the above