Question

The unit circle of the Nyquist plot transforms into 0dB line of the amplitude plot of the Bode diagram at

(a) 0 frequency

(b) Low frequency

(c) High frequency

(d) Any frequency

This question was posed to me in an interview.

My doubt stems from Polar Plots topic in section Frequency Response Analysis of Control Systems

Answer 1

Correct choice is (d) Any frequency

For explanation I would say: The unit circle of the Nyquist plot transforms into 0dB line of the amplitude plot of the Bode diagram at any frequency.