Control Systems Objectives Part 02
20 . Laplace transform of 1 is ππ¬.
21 . The Laplace transform of a unity function is ππ¬ .
22 . Under thermal and electrical system analogy charge is considered analogous to temperature.
23 . Viscous current coefficient-Reciprocal of resistance is the analogous pair under current force analogy.
24 . The Laplace transform of sinκt isκππ+κπ.
25 . Laplace transform of π‘nβ1<(πβ1) (n is positive integer) isπππ§
26 . The Laplace transform of e-2t isππ+π
27 . Laplace transform (used to switch a function from the time domain to the s-domain) method of solution is applicable to equations containing none of the above.
28 . When analogy between liquid level and electrical systems is drawn, voltage is considered as analogous to head.
29 . Under force-voltage analogy, viscous friction coefficient is analogous to resistance.
30 . The inverse Laplace transform of κπ (π 2+κ2) is πκπ [cosκt-1]
31 . The system with characteristic equation s4+3s3+6s2+9s+12=0 is unstable.
32. The characteristic equation s2+ 4s2+8s+12 represents a stable system.
33 . The impulse responses of systems are given below.sinκt represents an unstable system.
34 . A system with characteristic equation s3+14s2+56s+k=0 will be stable if0 0 and 784 β K 14 > 0 or 784 β K > 0 or K < 784 Therefore 0 < K < 784 is the required condition for the system to be stable.
35 . The characteristic equation of a system is s4+3s3+6s2+9s+12=0 . in order to ensure that the system be stable, K must be greater than zero a and less than 10.
36 . Fig. 20 represents the impulse response given by e-tsin3t.

37 . If a zero appears in the first column of the Routh table, the system is necessarily unstable.
38 . The roots of the characteristic equations of several systems are given below.2,-1,-3 roots represents unstable system.
39 . Which of the following characteristic equation represents a stable system s2+7s2+7s+46.
40 . For the characteristic equation 2s3+4s2+4s+12=0 the number of roots with positive real parts is two.