Thermometer is not the same thermometer

Invention of the thermometer

The word "thermometer" comes from two Greek words "thermos" for "warmth" or "heat on" and "metron", meaning "measure" together. A thermometer is thus an instrument for determining temperature.

Galileo put his studies on the change in the density of liquids at different heat effects the foundation for the development of a reliable instrument measuring the temperature. Although Galileo did not invent the thermometer is liquid, was to honor his fundamental research in the field of thermometry, called the Galileo thermometers to him.

Thermometer, as everyone knows them

On the principle of expansion and contraction of liquids are still working today most commercial thermometer. The best known is probably the thermometer, which is found in every well-stocked pharmacy cabinet. Swim in contrast to Galileo thermometer, in the vitreous body in a fluid-filled cylinders that raise depending on the heat off or on, we are now almost exclusively the hermetically sealed thermometer known.

In a transparent glass tube with constant uniform diameter is the measured liquid, usually mercury or alcohol. The fluid expands when heated and contracts when cooled back together. Based on the measurement scale, the identification of all thermometers can be read off the current temperature. Were both invented the mercury thermometer and the alcohol by the German physicist Gabriel Fahrenheit.

Temperature Units

Fahrenheit used as zero point the lowest temperature he could produce with an ice-salt freezing mixture. The freezing point of water under normal atmospheric pressure was adjusted to 32 degrees Fahrenheit (° F) determines the boiling point to 212 ° F.

Anders Celsius, however, presented for the freezing point of water 0 ° Celsius (° C) determined. The boiling point is exactly 100 ° C. Both scales are recognized worldwide, with the Fahrenheit scale is widely used in Anglo-Saxon countries.

As usual in physics, all units of a scale are divided into equal intervals. Only then can a reliable measurement and reached a correct display output.

Thermograph

During normal thermometers can be read only with the current temperature, it is possible with thermographs to record temperatures over a certain period of time. This meter is equipped with a writing essay documenting his findings on a rotating drum of paper. By the speed of the rotations to be measured time period is specified. They are used both scientific and industrial fields.

Thermo-hygrometer

Thermo-hygrometer measuring instruments are combined, the display shows not only the temperature but also indicates the current humidity. The measurement is made by a so-called moisture sensor that measures the water vapor in the air steam. They are used primarily in the areas where the combination can have unwanted effects of temperature and humidity. Examples might include: manufacturing or processing of food or growing plants. Of course, hygrometers are also used to create optimum climatic conditions within spaces in your home or office.

Pyrometer

The pyrometer, also called radiation thermometers based on the recognition that objects make heat radiation. The intensity of this radiation depends on the temperature of the object. Pyrometers allow rapid measurement and can be used for measurements of hazardous substances, as the temperature measurement is contactless via a laser. Pyrometers are also under the term "infrared thermometer" known. The display is usually issued in electronic form from the device.

Tip

There are a variety of thermometers that are used differently. Think about it before you buy a thermometer, for what purposes you want to use it. Besides the price also play safety aspects and the possibilities of diverse fields of a role. If you know what you need it, the first step is done to find just the thermometer, with which you will be satisfied for long.