-
Given a unity feedback system with open-loop transfer function
G(s) = K s(s + 1)(s + 2)
The root locus plot of the system is of the form
Correct Option: A
| G(s) = | ||
| s(s + 1)(s + 2) |
s3 + 3s2 + 2s + K = 0
from Routh Hurwitz criterion, we have
The K = 6 point is given by,
and 3(ω)2 + K = 0
⇒ ω = ± √2 j
Hence ω = ± √2 j. It intersects imaginary axis.
Since only plot (a) intersects imaginary axis, plot is the reasonable choice.
