56. Logarithmic amplifiers are used in :
(a) Adders
(b) Dividers
(c) Multipliers
(d) All of the above
57. Which of the following amplifier behaves like a :
(a) RF
(b) IF
(c) AF
(d) a and b both
58. In high frequency region, an amplifier behaves like a :
(a) Band pass filter
(b) Low pass filter
(c) High pass filter
(d) Any of the above
59. Which amplifier will be preferred gain ?
(a) Darlington’s pair
(b) Cascade amplifier
(c) Cascode amplifier
(d) Depends on the circuitry
60. Class B amplifier has less efficiency compared to :
(a) Class A
(b) Class AB
(c) Class C
(d) Class A, AB and C
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