A Best Way To Crack Gorenment Job Exams

ECE Objective Questions { Operational Amplifier and Its Applications }

71. An AF amplifier is shielded to
A. keep the amplifier cool
B. protect from rusting
C. prevent induction due to stray magnetic fields
D. none of the above

72. The pulsating d.c. appliedto power amplifier causes
A. burning of transistor
B. hum in the circuit
C. excessive forward voltage
D. none of the above

73. The disadvantage of impedance matching is that it
A. gives distorted output
B. gives low power output
C. requires a transformer
D. none of the above

74. If the gain versus frequency curve of a transistor amplifier is not flat, then there is _____ distortion.
A. amplitude
B. intermodulation
C. frequency
D. none of the above

75. The most costly couping is ____ coupling.
B. direct
C. impedance
D. transformer

76. An oscillator converts
A. a.c. power into d.c. power
B. d.c. power into a.c. power
C. mechanical power into a.c. power
D. none of the above

77. In an LC transistor oscillator, the active device is
A. LC tank circuit
B. biasing circuit
C. transistor
D. none of the above

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