Alkoholilämpömittarin

An alkoholilämpömittari, or alcohol thermometer, is a type of liquid-in-glass thermometer that uses alcohol as its thermometric fluid. Unlike mercury thermometers, which were common in the past, alcohol thermometers are less toxic and can measure temperatures below the freezing point of mercury. The alcohol is typically dyed a bright color, such as red or blue, to make it more visible within the glass tube.

The principle of operation is based on the thermal expansion of alcohol. As the temperature increases, the alcohol in the bulb expands and rises up the narrow capillary tube. Conversely, as the temperature decreases, the alcohol contracts and falls back down the tube. Markings on the glass tube, calibrated against known temperature points, allow for the reading of the temperature.

Alcohol thermometers are often used for measuring ambient temperatures, such as in weather stations or for general room temperature indication. They are also found in applications where a wider temperature range than mercury thermometers can provide is needed, particularly at very low temperatures. Due to their simplicity, low cost, and non-toxicity, they remain a practical choice for many everyday temperature measurement needs.