31. A device that converts chemical energy to electrical energy is called a:
A. solar cell
B. thermocouple
C. chemical cell
D. electric device
E. None of the above
32. Suppose the peak value of a sinusoidal voltage is 50 V. What is the rms value?
A. 37.4 V
B. 35.4 V
C. 38.74 V
D. 30.4 V
E. None of the above
33. What is the difference between a conductor and an insulator?
A. A conductor allows current to flow much easier than an insulator does
B. An insulator has an excessive number of free electrons, while a conductor has a few free electrons or none at all
C. An insulator allows current to flow much easier than a conductor does
D. The difference between conductors and insulators depends on how they are used
E. None of the above
34. A circuit has two different voltage sources that are connected in a series-aiding form. If the sources are rated at 6 V and 9 V, what is the total source voltage?
A. 15 V
B. 16 V
C. 7.5 V
D. 8 V
E. None of the above
35. At room temperature an intrinsic semiconductor has
A. a few free electrons and holes
B. many holes
C. many free electrons
D. No holes
E. None of the above