Davies Publishing SPI Practice Test

A transducer is a device that converts energy from one form into another. This fundamental role underlies how sensors and actuators operate: a microphone turns sound energy into an electrical signal, a loudspeaker does the reverse by transforming electrical energy into sound, a light sensor converts light into an electrical signal, and a pressure sensor translates mechanical energy into voltage. The other options describe circuit behaviors or properties that aren’t about transforming energy forms—opening circuits to adjust impedance, storing energy temporarily, or filtering signals are functions of other components or processing steps, not the core purpose of a transducer.