Question

The continuous time system described by 2 y(t) = x (t^2) is

(a) Causal, linear and time varying

(b) Causal, non-linear and time varying

(c) Non causal, non-linear and time-invariant

(d) Non causal, linear and time-invariant

I had been asked this question in an online interview.

The above asked question is from The z- and s-Domain Relationship topic in section Digital Control Systems of Control Systems

Answer 1

The correct choice is (d) Non causal, linear and time-invariant

Best explanation: Y (t) depends upon the future value therefore the system is anticipative and hence is not causal. But as it follows the superposition theorem so it is linear.