91. Positive feedback results in ________.
(a) decreased voltage gain
(b) increased voltage gain
(c) oscillation in the circuit
(d) None of the above
92. With feedback, , the overall gain of the circuit is reduced by a factor ________ where A is the gain without the feedback.
(a)
(b) A
(c) A
(d) 1 + A
93. Series-feedback connections tend to ________ the input resistance. Shunt feedback connections tend to ________ the input resistance.
(a) decrease, increase
(b) increase, decrease
(c) increase, increase
(d) decrease, decrease
94. What is the gain at the origin of the Nyquist plot?
(a) Zero
(b) A negative value
(c) A positive value
(d) Undefined
95. In a Nyquist plot, as the frequency increases, the phase shift between input and output signals ________.
(a) remains the same
(b) decreases
(c) increases
(d) None of the above
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