288.  Amplidyne is a type of
A. Magnetic amplifier
B. Rotating amplifier
C. Electronic amplifier
D. Synchro transformer

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289.  A sampled signal has z-transform Tz R(z) ?2 ? Which of the following (z ? 1)time-domain signals does it represent?
A. Exponential
B. Step
C. Ramp
D. Sinusoidal

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290.  Consider the signals xi(t) = 2 sin nt + cos 4nt and x2(t) = sin 5nt + 3 sin 13 nt :
A. Both the signals are periodic
B. Both the signals are not periodic
C. xi is periodic, but x2 is not periodic
D. xi is not peiodic, but x2 is periodic

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291.  Given a unity feedback system with G(s) , the value of K for s(s + 4) damping ratio of 0.5 is
A.1
B.16
C.4
D.2

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292.  A unity feedback control system has forward path transfer function G(s) given by C(s)? , 10(1 + s) s`(s + 12) (s + 5) The steady-state error due to unit parabolic input r(t)= ?2 U(t) is t2
A. zero
B.0.5
C.1
D. infinite

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293.  For the control system with K(s + 2) G(s) H(s) s(s` + 2s + 3) the type number is
A.2
B.1
C.4
D.C 3

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294.  The root locus plot of a system having open loop transfer function K(s + 10) (s + 70) G(s) H(s) ? s' (s + 100) (s + 200) will have angle of asymptotes as
A. 60?, 1000
B. 60?, 180?, 300?
C. 60?, 120?, 180?
D. 60?, 90?, 120?

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