Which device operates on the principle that metals change electrical resistance with temperature?

The device that operates on the principle that metals change electrical resistance with temperature is the Resistance Temperature Detector (RTD). RTDs are designed to measure temperature based on the characteristic that the electrical resistance of certain metals, such as platinum, varies in a predictable manner with changes in temperature. As the temperature increases, the resistance of the metal also increases. This relationship is linear over a certain temperature range, allowing for accurate temperature measurements.

RTDs are widely used in industrial applications because of their precise readings and stability over time. Unlike other temperature measurement devices that may rely on different principles, an RTD directly translates temperature changes into resistance changes, enabling detailed and accurate readings that can be easily calibrated and interpreted.

By understanding how RTDs function, it becomes clear why they are the correct choice in the context of devices measuring temperature through electrical resistance, providing a reliable and effective means of monitoring thermal conditions in various processes.