Question

A unit step is applied at t=0 to a first order system without time delay. The response has the value of 1.264 units at t=10 mins, and 2 units at steady state. The transfer function of the system is_____________

(a) 3/(1+600s)

(b) 2/(1+500s)

(c) 5/(1+220s)

(d) 2/(1+600s)

This question was posed to me during an online exam.

I would like to ask this question from Time Response of First Order Systems topic in chapter Time Response Analysis, Design Specifications and Performance Indices of Control Systems

Answer 1

Right choice is (d) 2/(1+600s)

The explanation: a(t)= k[1-e^^-t/T]

  K=2

  0.632= 1-e^^-10/T

  T=600 sec

  G(s)=2/(1+600s).