A unity negative feedback control system is found to have a gain margin of 20 dB. The Nyquist plot of the

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A unity negative feedback control system is found to have a gain margin of 20 dB. The Nyquist plot of the system

(A) crosses the real axis at +0.1 (B) crosses the real axis at -0.1.

(C) crosses the imaginary axis at -0.1 (D) crosses the imaginary axis at +0.1

A unity negative feedback control system is found to have a gain margin of 20 dB. The

Nyquist plot of the system crosses the real axis at -0.1.

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