309. The dopen loop transfer function of a unity feedback system is given by 3e-2G(s) - s(s+ 2) The gain and phase crossover frequencies in rad/sec are, respectively

A. 0.63 and 1.26

B. 0.632 and 0.485

C. 0.485 and 0.632

D. 1.26 triA and 0.632 V

310. The dopen loop transfer function of a unity feedback system is given by 3e-2G(s) - s(s+ 2) Based on the above results, the gain and phase margins of the system will be

A. -7.09 and 87.5?

B. 7.09 and 87.5?

C. 7.09dB and -87.50

D. -7.09dB and -87.5?

311. The open-loop transfer function of a unity-gain feedback control system is given by G(s)= (s +1) (s + 2) The gain margin of the system in dB is given by

A.0

B.1

C.20

D.5

312. For the function of a complex variable W = In Z (where, W = u + jv and Z = x + jy), the u = constant lines get mapped in 1-plane as

A. set of radial straight lines

B. set of concentric circles

C. set of confocal hyperbolas

D. set of confocalellipses

313. Consider two transfer functions Gi(s)=s2+as+b and G2(s) =S2 -i-as+b The 3-dB bandwidths of their frequency responses are, respectively

A. Ara7-711) ,A/T-74b

B., VT-71b

C., Nra-f=111;

D.41) 421

314. The Nyquist plot of G (Jm) H (Jo)) for a closed loop control system, passes through (-1, j0) point in the CH plane. The gain margin of the system in dB is equal to

A.infinite

B. greater than zero

C. less than zero

D. zero

315. The transfer function of a phase-lead compensator is given by 1+ 3Ts 1+Ts where T > 0 The maximum phase-shift provided by such a compensator is It

A.1

B.2

C.3

D.4

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