Alberta Boilers Safety Association (ABSA) Practice Test

The choice indicating that resistance increases as temperature increases is correct because it reflects the fundamental operational principle of Resistance Temperature Detectors (RTDs). These devices utilize the property of metals, typically platinum, which exhibit a predictable increase in electrical resistance with rising temperature. In RTDs, this resistance change with temperature is a linear function over a significant range, making them reliable for precise temperature measurements. As the temperature of the RTD increases, the atoms within the metal vibrate more, which impedes the flow of electrons. Thus, the electrical resistance increases, providing a measurable parameter for temperature readings. This principle is fundamental not only to temperature measurement but also to the design and application of temperature sensors in various industrial processes, ensuring accurate and reliable temperature monitoring.