Control Systems None of the poles of a linear control system lie in the right half of s plane. For a bounded input, the output of this system

could be unbounded.
tends to zero.
always bounded.
none of these.

Control Systems Number of sign changes in the entries in 1st column of Routh array denotes the no. of

open loop poles in RHP.
roots of characteristic polynomial in RHP.
zeroes of system in RHP.
open loop zeroes in RHP.

Control Systems A cascade of three linear time invariant systems is causal and unstable. From this we conclude that

at least one system is unstable and at least one system is causal.
at least one system is causal and all systems are unstable.
the majority are unstable and the majority are causal.
each system in the cascade is individually caused and unstable.

Control Systems In the integral control of the single area system frequency error is reduced to zero. Then

integrator o/p decreases but speed changer position moves up.
integrator o/p decreases and speed changer position comes down.
integrator output and speed changer position attain a constant value.
integrator o/p increases but speed changer position comes down.

Control Systems When the polynomial is Routh Hurwitz,

none of these.
all zeroes lie in the right half of the s-plane.
the function is not real.
the roots of function have real parts which are to be zero/negative.