Definition
A gas thermometer is a device that measures temperature based on the principle that the volume or pressure of a gas changes with temperature. 🌡️ It typically uses a gas like helium or hydrogen in a closed container. The expansion or contraction of the gas indicates the temperature. Think of it like a sensitive balloon that inflates or deflates with heat. Gas thermometers are known for their accuracy and are often used as a standard for calibrating other thermometers. They're a reliable way to gauge the temperature of the universe.