# Electronic Principles – Section 2

36. What is the smallest number of polarities required for current flow?

A. One – a negative terminal
B. Two – a negative terminal and a positive terminal
C. Three – negative, positive and neutral terminals
D. Four – two negative and two positive
E. None of the above

Correct Answer:  B. Two – a negative terminal and a positive terminal

37. A diode is in series with 220W. If the voltage across the resistor is 4V, what is the current through the diode?

A. 55 A
B. 55.86 A
C. 18.2 mA
D. 16.3 mA
E. None of the above

38. Two diodes are in series. The first diode has a voltage of 0.75 V and the second has a voltage of 0.8 V. If the current through the first diode is 500 mA, what is the current through the second diode

A. 11 mA
B. 12 mA
C. 10 mA
D. 14 mA
E. None of the above

39. The graph of current gain versus collector current indicates that the current gain

A. varies enormously
B. is constant
C. varies slightly
D. equals the collector current divided by the base current
E. None of the above

Correct Answer:  D. equals the collector current divided by the base current

40. Which one of the following statements is true for the currents in a parallel RL circuit?

A. The total current is equal to the sum of the currents through the resistance and inductance
B. The current always has the same amplitude and phase for every part of the circuit
C. The total current is less than the sum of the currents through the resistance and inductance
D. The total current leads the total voltage by less than 90
E. None of the above

Correct Answer:  C. The total current is less than the sum of the currents through the resistance and inductance