Question

Why unstable systems are considered to be impractical?

(a) None of the mentioned

(b) Output decreases with time

(c) Output reaches fixed value

(d) Output increases with time

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This question is from Closed-Loop Frequency Response and Circuit Stability topic in portion Practical Limitations of Op Amp Circuits of Linear Integrated Circuits

Answer 1

Unstable systems are impractical because their output increases with time, making them unsuitable for real-world applications. In an unstable system, any disturbance or noise will cause the output to grow indefinitely, which can lead to:

1. Equipment damage

2. Uncontrolled behavior

3. Inability to maintain steady state

Answer: (d) Output increases with time