Question

The output of a feedback control system must be a function of

(a) Reference and output

(b) Reference and input

(c) Input and feedback signal

(d) Output and feedback signal

I got this question during an interview for a job.

My question is taken from The Approximation of Higher-Order Systems by Lower-Order in portion Time Response Analysis, Design Specifications and Performance Indices of Control Systems

Answer 1

The correct answer is:

(c) Input and feedback signal

In a feedback control system, the output depends on both the input (the reference or desired output) and the feedback signal (which is the output measured and fed back into the system to adjust the input). The feedback loop adjusts the system's behavior to minimize the difference between the actual output and the reference input.