Closed-loop systems use feedback to reduce errors and improve stability.

• A. Uncertain
• B. Not applicable
• C. False
• D. True

Answer: (D)

Closed-loop control relies on feedback to correct errors and regulate the output. A sensor measures what the system is actually doing, a comparison to the desired value generates an error signal, and the controller uses that error to adjust the actuator. This continuous adjustment reduces the difference between the target and the actual output, so disturbances are corrected and the system settles more reliably. That’s why it’s true: feedback-driven correction leads to lower steady-state error and improved stability. Think of a thermostat keeping room temperature steady: it constantly senses temperature and turns the heating or cooling on or off to maintain the setpoint. Negative feedback is the usual way this stabilizes the system, whereas positive feedback would tend to amplify deviations. The specific controller (like proportional, integral, and derivative parts) shapes how quickly and smoothly the corrections occur, balancing responsiveness with stability.