267. Feedback control systems are

A. insensitive to both forward-and feedback-path parameter changes.

B. less sensitive to feedback-path parameter changes than to forward-path parameter changes.

C. less sensitive to forward-path parameter changes than to feedback-path parameter changes.

D. equally sensitive to forward-and feedback-path parameter changes.

268. A unity feedback system has open-loop transfer function G(s). The steady-state error is zero for

A. step input and type-1 G(s)

B. ramp input and type-I G(s)

C. ste input and type-G(s)

D. ramp input and type-0 G(s)

269. A linear time-invariant system initially at rest, when subjected to a unit-step input, gives a response y(t) = te-t, t> 0. The transfer function of the system is.

A. always stable

B. marginally stable

C. unstable with one pole on the right half s-plane

D. unstable with two poles on the right half s-plane

270. The state transition matrix for the system X = AX with initial state X(0) is

A. (sl - A)-1

B. eAt X(0)

C. Laplace inverse of [(s1)] -

D. Laplace inverse of [(sI - A)' x(o)]

271. For the system X = [o,5,0]which of the following statements is true?

A. The system is controllable but unstable

B. The system is uncontrollable and unstable

C. The system is controllable and stable

D. The system is uncontrollable and stable

272. A lead compensator used for a closed loop controller has the following transfer function For such a lead compensator

A.a

**B.b**

C. a > Kb

D.a

273. A second order system starts with an initial condition of without any external input. The state transition matrix for the system is given by [e-2t 0 e-t . The state of the system at the end of 1 second is given by

A. [0.271] 1.100 i 02711

B. [0.3681[0.1351

C. [0.736,0.1351

D.1.1

C. a > Kb

D.a

273. A second order system starts with an initial condition of without any external input. The state transition matrix for the system is given by [e-2t 0 e-t . The state of the system at the end of 1 second is given by

A. [0.271] 1.100 i 02711

B. [0.3681[0.1351

C. [0.736,0.1351

D.1.1

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