225. Consider the unit-step response of a unity-feedback control system whose open-loop transfer function is G(s) = s(s + 1) The maximum overshoot is equal to
A.0.143
B.0.153
C.0.163
D.0.194
226. For a feedback control system of type 2, the steady state error for a ramp input is
A. infinite
B. constant
C. zero
D. indeterminate
227. The close-loop transfer function of a control system is given by ?C(s) R(s) 1 + s For the input r(t) = sin t, the steady state value of c(t) is equal to f(t) is
A. infinity
B. zero
C. one
D. none of these
228. The impulse response of an initially relaxed linear system is e-2t U(t). To produce a response of te-2t U(t), the input must be equal to1
A. 2e-t U(t)
B. ?2C't U(t)
C. e-2t U(t)
D. e-t U(t)
229. The closed-loop transfer function control system is given byC(s)2(s - 1) R(s)(s + 2) (s + 1) For a unit step input the output is
A. 3e-2t 4e-i _
B. -3e-2t - 4e-t + 1
C. zero
D. infinity
230. For the characteristic equation s2 + 4.8s + 72 = 0, the damping ratio and natural frequency respectively are
A. 0.212, 8.1 rad/s
B. 0.283, 8.48 rad/s
C. 0.299, 8.66 rad/sec
D. none of the above
231. The transfer function of a control system is given as T(s) ? s + 2s+K where K is the gain at the system in radian / amp. For this system to be critically damped, the value of K should be
A.1
B.2
C.3
D.4
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