Which term describes a closed-loop system that produces a force to position an object according to input information?

• A. Servo
• B. Servomechanism
• C. Synchroscope
• D. Transformer

Answer: (B)

A servomechanism is a closed-loop control system that uses feedback to position an object according to an input command. The system compares the desired position with the actual position, generates an error signal, and uses an actuator to apply the force needed to reduce that error. This continuous feedback and adjustment lets the mechanism reach the commanded position accurately and hold it, even in the presence of disturbances. The term described fits best because it encompasses both the control logic and the actuation that moves the object, not just a single component. In practice, the shorthand “servo” is often used for the actuator part, but the full concept is a servomechanism. The other terms refer to different devices: a synchroscope deals with synchronizing rotating machines, and a transformer transfers electrical energy without positional control or closed-loop feedback.