A thermometer has a glass tube sealed at both ends and is partly filled with a liquid like mercury or alcohol. As the temperature around the thermometer’s bulb heats up, the liquid rises in the glass tube. … When it is hot, the liquid inside the thermometer will expand and rise in the tube.
Additionally, how does a fluid expansion temperature measuring device work?
The basic principle in pressure thermometers are when liquids, gases or vapours are heated, they will expand, when they are cooled, it will contract. … This difference in pressure will give the temperature change.
Besides, what are 3 types of thermometers?
What Are the Different Ways a Thermometer Can Be Used?
- Axillary Thermometers (under your arm)
- Oral Thermometers (under your tongue)
- Tympanic Thermometers (in your ear)
- Rectal Thermometers (in your rectum)
- Temporal Artery or Infrared Thermometers (across your forehead)
What are the two types of thermometers?
Types of thermometer
- Digital thermometers. Digital thermometers are quick to use, reasonably accurate and can be used under the armpit (always use the thermometer under the armpit with children under 5). …
- Ear (or tympanic) thermometers. …
- Infared thermometers. …
- Strip-type thermometers. …
- Mercury thermometers.
What is a thermometer used for?
A thermometer is a device used for measuring temperature.
What is commonly used in liquid filled thermometer?
Mercury is usually used in liquid-filled thermometers, since it remains liquid in the temperature range from –38° to 356°C at normal pressure and up to 750°C with a small increase in pressure, which is attained by filling the bore with nitrogen.
What is fluid thermometer?
In a mercury thermometer, a glass tube is filled with mercury and a standard temperature scale is marked on the tube. With changes in temperature, the mercury expands and contracts, and the temperature can be read from the scale. Mercury thermometers can be used to determine body, liquid, and vapor temperature.
Why do thermometers use liquid?
Most metals are good conductors of heat and they are solids at room temperature. Mercury is the only one in liquid state at room temperature. It’s used in thermometers because it has high coefficient of expansion. Hence, the slightest change in temperature is notable when it’s used in a thermometer.