What type of sensor consists of two dissimilar wires that create a voltage when heat is applied?

A thermocouple consists of two dissimilar metal wires joined at one end, which creates a voltage when subjected to a temperature difference. This phenomenon is known as the Seebeck effect. When heat is applied to the junction where the two wires are connected, it generates a voltage that can be measured and is directly related to the temperature difference between the junction and the other ends of the wires. Thermocouples are widely used for temperature measurement in various applications, making them essential tools in power engineering and other fields.

In contrast, a thermistor is a type of resistor whose resistance varies significantly with temperature, but it does not involve two dissimilar wires creating a voltage. A transducer is a broader term that refers to devices that convert one form of energy into another, which may include various types of sensors. A manometer measures pressure and uses fluid columns to display pressure readings, rather than generating voltage based on temperature. Thus, thermocouples are uniquely identified by their specific mechanism of voltage generation through thermal effects.