1. The loop transfer function of a feedback control system is given by

Number of asymptotes of its root loci is :

(a) 1

(b) 2

(c) 3

(d) 4

2. A unity feedback system has

In the root-locus, the break-away point occurs between :

(a) s = 0 and -1

(b) s = -1 and -∞

(c) s = -1 and -2

(d) s = -2 and -∞

3. If the characteristic equation of a closed-loop system is

the centroid of the asymptotes in root-locus will be :

(a) zero

(b) 2

(c) – 1

(d) – 2

4. The intersection of root locus branches with the imaginary axis can be determined by the use of :

(a) nyquist criterion

(b) polar plot

(c) routh’s criterion

(d) none of the above

5. The characteristic equation of a feedback control system is

The number of roots in the right half of s-plane are :

(a) zero

(b) 1

(c) 2

(d) 3