# Electronic Principles – Section 4

26. Which one of the following statements applies to common auto batteries?

A. Auto batteries are primary wet-cell batteries
B. Auto batteries are secondary wet-cell batteries
C. Auto batteries are secondary dry-cell batteries
D. Auto batteries are primary dry-cell batteries
E. None of the above

Correct Answer:  B. Auto batteries are secondary wet-cell batteries

27. Which one of the following equations most directly determines the power dissipation of a resistance when you know the power dissipation of a resistance when you know the voltage drop and current?

A. P = IE
B. P = E2/R
C. P = I2R
D. I = P/E
E. None of the above

Correct Answer:  A. P = IE

28. If N1/N2 = 2, and the primary voltage is 120 V, what is the secondary voltage?

A. 0 V
B. 36 V
C. 40 V
D. 60 V
E. None of the above

Correct Answer:  D. 60 V

29. A device that converts light energy to electrical energy is called a:

A. thermocouple
B. solar cell
C. photodiode
D. phototransistor
E. None of the above

Correct Answer:  B. solar cell

30. How much current flows through a 60-W light bulb that is operating at 120 V?

A. 0.5A
B. 180 A
C. 2 A
D. 7200 A
E. None of the above

Correct Answer:  A. 0.5A