Question

Given a system function H(s) = \(\frac{1}{s+3}\). Let us consider a signal sin 2t. Then the steady state response is ___________

(a) \(\frac{1}{8}\)

(b) Infinite

(c) 0

(d) 8

I have been asked this question during an interview for a job.

Asked question is from Properties of ROC in section Laplace Transform and System Design of Signals and Systems

Answer 1

Correct choice is (c) 0

For explanation I would say: H(s) = \(\frac{V(s)}{J(s)}\)

= \(\frac{1}{s+3}\)

V(s) = \(\frac{1}{s+3}\). J(s)

J(s) = L (sin 2t) = \(\frac{2}{s^2+4}\)

V (s) = \(\frac{1}{s^2+4} . \frac{2}{s+3}\)

VSS = lims→0 sV(s)

= 0.