46. In an emitter follower, we employ …… negative current feedback
(a) 50%
(b) 25%
(c) 100%
(d) 75%
47. An amplifier has an open loop voltage gain of 1,00,000. With negative voltage feedback, the voltage gain is reduced to 100. What is the sacrifice factor ?
(a) 1000
(b) 100
(c) 5000
(d) none of the above
48. In the above question, what will happen to circuit performance ?
(a) distortion is increased 1000 times
(b) input impedance is increased 1000 times
(c) output impedance is increased 1000 times
(d) none of the above
49. The non-linear distortion of an amplifier is D without feedback. The amplifier has an open-loop voltage gain of Av and feedback fraction is mv. With negative voltage feedback, the non-linear distortion will be …….
(a) D (1 + Av mv)
(b) D (1 – Av mv)
(c) (1 + A m)/D
(d) 1 D/(1 + Avmv)
50. The output and input voltages of an emitter follower have a phase difference of …….
(a) 180º
(b) 90º
(c) 0º
(d) 270º
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