Final answer:
The common sensing element in an electronic t-stat is a thermistor, which changes resistance with temperature and converts these changes into electrical signals for precise temperature control.
Step-by-step explanation:
The common sensing element used in an electronic thermostat (t-stat) is a thermistor. A thermistor is a type of resistor whose resistance changes with temperature. In electronic thermostats, thermistors are utilized for their precise response to temperature fluctuations, converting changes in resistance into electrical signals to accurately measure and control temperature. This small, sensitive component makes it ideal for maintaining the desired environmental temperature, acting as the sensor component of a homeostatic mechanism.
While older or analog thermostats might use a bimetallic strip that bends with temperature changes, electronic thermostats rely on the more accurate and responsive thermistors to perform their function.