Critère de Nyquist (1)

Which principle specifies the relationship between enclosure of poles & zeros by s-plane contour and the encirclement of origin by q(s) plane contour?

If a Nyquist plot of G (jω) H (jω) for a closed loop system passes through (-2, j0) point in GH plane, what would be the value of gain margin of the system in dB?

For Nyquist contour, the size of radius is _______

Consider a feedback system with gain margin of about 30. At what point does Nyquist plot crosses negative real axis?

According to Nyquist stability criterion, where should be the position of all zeros of q(s) corresponding to s-plane?

If the system is represented by G(s) H(s) = k (s+7) / s (s +3) (s + 2), what would be its magnitude at ω = ∞?

Consider the system represented by the equation given below. What would be the total phase value at ω = 0? 200/[s3 (s + 3) (s + 6) (s + 10)].

Due to an addition of pole at origin, the polar plot gets shifted by ___ at ω = 0 ?

In polar plots, if a pole is added at the origin, what would be the value of the magnitude at Ω = 0?

In polar plots, what does each and every point represent w.r.t magnitude and angle?