Control Systems Objectives Part 05
81 . The value of K for the stability in the following should be ππ< K < 1
Ks4+Ks3+s2+s+1=0
82 . Actuating signal will become zero when feedback signal and reference signals are equal.
83 . The transfer function of a system is the ratio of Laplace transform of the output variable to that of input variable.
84 . The dc gain of the system represented by s transfer functionP(s) = 1s+1 is 1
85 . The equation for a servo-mechanism damped solely by pure viscous friction, is given by
(10D2+20D+1000)κo =1000κiWhere κo = load shaft displacement, radians.
κi = input shaft displacement, radiansThe value of damping ratio will be 0.1
86 . Transfer function can be obtained from signal flow graph.
87 . The transfer function of a system is given byP(s) = 2s+2For κ=10, the gain will be 0.196
88 . In the above case the phase shift will be -tan-1 5.
89 . Reference input minus the primary feedback is actuating signal.
90 . The transfer function is applicable to linear and time invariant systems.
91 . The dc gain of the system represented by the transfer functionP(s) =(s+8)(π +2)(s+4) is 1.
92 . The input which is established or varied by some means external to and independent of the feedback control system is known as command.
93 . The impulse response of a certain system is the sinusoidal signal sint. The transfer function is πππ+π
94 . For a system has transfer functionP(s) =2(π +2)The gain for κ=2 will be 0.707
95 . In the above case, the phase shift will be –45o.
Questions 96 to 99 refer to Fig. 24
A control system is composed of components whose transfer functions are as specified in the block diagram.

96 . Which of the following is the expression for the closed loop transfer functions? πππ+ππ+ππ.
97 . At what frequency does the output variable oscillate in responding to a step command before reaching a steady gate? 3 rad/sec.
98 . In the above case the maximum percent overshoot is 35%.
99 . Time required for to output to reach within percent of steady state in equation is 5 seconds.
Question 100 to 103 refer to data given below:
The measurements made on a servo mechanism show the output response to be
πΆ(π‘)πo= 1 β 1.66e-8t sin (6t+37) where the input is a step displacement of magnitude ro
100 . The natural frequency of the system in radians per second is 10 radians per second.