The polar plot of the open loop transfer function of a feedback control system intersects the real axis at -2. The gain margin of the system is
A. -5dB
B. 0dB
C. -6dB
D. 40dB
Answer:C
The polar plot of the open loop transfer function of a feedback control system intersects the real axis at -2. The gain margin of the system is
A. -5dB B. 0dB C. -6dB D. 40dB
Explanation: Gain margin of the system is inverse of the intersect on the real axis and calculated in decibels.