THERMOMETER

In determining a thermometer scale, selected what was referred to the points anyway. Usually the points are the freezing point and boiling point at normal atmospheric pressure. XVIII century Swedish astronomer, Andres Celsius thermometer illustrate by giving a value of 100 for the boiling point of water and the value 0 to its freezing point. range from 0 to 100 was divided into 100 parts called degrees.

It is unclear whether Andres Celsius thermometer to develop this thermometer by himself. Some scientists link it with the seventeenth-century biologist Charles Linnaes. It called the centigrade thermometer ("one hundred degrees") or Thermometer Celcius and in widespread use. German physicists in the early seventeenth century Daniel Gabriel Fahrenheit chose a another fixed point. The lowest temperature in the show by a mixture of ice and salt called 0 degrees. For the normal human body temperature of 96 degrees gave the value. after his death, freezing and boiling points in a row give the value 32 degrees and 212 degrees. Fahrenheit thermometer is widely used in countries that speak english. Centigrade thermometer is more simple and practical has long been in use in mainland Europe and is now accepted worldwide. Special Thermometer.

There are several types of thermometers. Type of thermometer is widely known as "clinical thermometer" used to determine body temperature. For most people, normal body temperature is around 37 degrees Celsius or 98.6 degrees Fahrenheit. One of the privileges of the clinical thermometer is that the column of mercury remain in the line of the highest temperature reached. Of course, this is unbelievably desirable because, otherwise, the temperature will be changed in the period between the decision from the body and when reading.

Differential thermometer used for temperature measurement is very precise. This tool can be adjusted using a fine mercury backup to cover certain parts such as 5 degrees of the whole distance, to the nearest 1/100 degrees

To measure very small differences in temperature, or termopail termokupel used. In this tool, two types of metals such as iron and copper are combined in a circuit formed of two common ground. If one intersection is hotter than the others, will be generated electromotive power. These forward current through the circuit. Electromotive power up if the difference in temperature increases