calery (in English: Calorie) for the first time in 1824 AD by Nicholas Clement [1] was defined as a unit of heat. Calories from the Latin word calor, meaning heat is taken. Between 1841 and 1867 the word was added to the cultures, English and French.
Calorie is defined in two ways:
Small calories or Grmkalry (symbol: cal) that is equal to the amount of energy required to raise the temperature of 1 gram of water 1 degree Celsius in air pressure as 1 atm.
Big or Kylvgrmkalry calories (kcal) (symbol: Cal [2] or kcal) that the calories (in English: food calorie) and its value is equal to the amount of energy required to raise the temperature ° ۱ C 1 kg of water.
۱ large calorie is equal to 1,000 calories a little. (The food we eat energy is measured by calories [3])
These units were used for many years in metric measurement system. In 1948, the scientific community decided that because of the heat (such as) energy is transferred to the unit of SI [4] for the same Joule heat should be.
۱ small calorie is approximately equal to 4. 2 J (exactly 4. 1868 joules [5])
۱ large calorie is approximately equal to 4. 2 is kJ.
A calorie is the amount of heat (energy) required for the temperature of one gram of water from 14. 5 degrees to 15. 5 ° C increase.