A Bellows-type sensor responds to a change in which parameter?

A Bellows-type sensor responds to a change in which parameter?

• A. Temperature
• B. Humidity
• C. Pressure
• D. Flow

Answer: (C)

A Bellows-type sensor is designed to detect pressure changes. The flexible bellows expands or contracts as the pressure difference across its walls changes. That mechanical deflection is then translated by a connected mechanism or transducer into a readable pressure value. Temperature or humidity don’t directly drive the bellows in the sense of measuring those quantities; they might influence readings indirectly through material properties or environmental effects, but the essential signal the bellows responds to is pressure. Flow isn’t measured directly by this device either; it’s the pressure within the system that the bellows responds to, and flow may cause pressure changes but the sensing element is responding to pressure itself.