31. Thermal run away of a transistor occurs when
a. heat dissipation from transistor is excessive
b. transistor joint melt due to high temperature
c. there is excessive leakage current due to temperature rise
d. none of the above

32. The leakage current in CB configuration may be around
a. few micro amperes
b. few hundred micro amperes
c. few milli amperes
d. few hundred milli amperes

33. The input and output signals for CE amplifier are always
a. equal
b. inphase
c. out of phase
d. complementary to each other

34. As compared to a CB amplifier , a CE amplifier has
a. lower current amplification
b. higher current amplification
c. lower input resistance
d. higher input resistance

35. In a resistance loaded RC coupled amplifier the dc component is blocked by
a. Transistors
b. Cc
c. Rb
d. Rc

36. Which junction transistor is prefered for high input and low output impedance?
a. common emitter
b. common base
c. common collector
d. any of the above

37. Common base configuration is little used because
a. it has low input impedance
b. it has high input impedance
c. it does not heat up
d. it has very high gain

38. Common emitter transistor has
a. high current and high voltage gain
b. low current gain and low voltage gain
c. high current gain and low voltage gain
d. low current and voltage gain

39. Which of the following circuit would be preferred for a 455 kHz IF amplifier?
a. resistance loaded
b. double tuned transformer
c. video amplifier
d. Class c

40. A FET has a gate source bias of _ 2V The ac input signal is+- 1.2 V. The class of operation will be
a. A
b. B
c. C
d. AB