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Fire is the rapid oxidation of a material (the fuel) in the exothermic chemical process of combustion, releasing heat, light, and various reaction products. [1] [a] At a certain point in the combustion reaction, called the ignition point, flames are produced.
Fire is one of the four classical elements in ancient Greek philosophy and science. It was commonly associated with the qualities of energy, assertiveness, and passion. In one Greek myth, Prometheus stole fire from the gods to protect the otherwise helpless humans, but was punished for this charity.
The four properties are cohesion (water), solidity or inertia (earth), expansion or vibration (air) and heat or energy content (fire). He promulgated a categorization of mind and matter as composed of eight types of " kalapas " of which the four elements are primary and a secondary group of four are colour, smell, taste, and nutriment which are ...
[citation needed] Fire was used to clear out caves before living in them, helping to begin the use of shelter. [38] The many uses of fire may have led to specialized social roles, such as the separation of cooking from hunting. [39] The control of fire enabled important changes in human behavior, health, energy expenditure, and geographic ...
Flames of charcoal. A flame (from Latin flamma) is the visible, gaseous part of a fire.It is caused by a highly exothermic chemical reaction made in a thin zone. [1] When flames are hot enough to have ionized gaseous components of sufficient density, they are then considered plasma.
Some of the earliest theories of life were materialist, holding that all that exists is matter, and that life is merely a complex form or arrangement of matter. Empedocles (430 BC) argued that everything in the universe is made up of a combination of four eternal "elements" or "roots of all": earth, water, air, and fire. All change is explained ...
The alchemist and physician J. J. Becher proposed the phlogiston theory.. The phlogiston theory, a superseded scientific theory, postulated the existence of a fire-like element dubbed phlogiston (/ f l ɒ ˈ dʒ ɪ s t ən, f l oʊ-,-ɒ n /) [1] [2] contained within combustible bodies and released during combustion.
The book is considered the founding work of thermodynamics. [2]: viii It contains the preliminary outline of the second law of thermodynamics.Carnot stated that motive power is due to the fall of caloric (chute de calorique) from a hot to a cold body, which he analogized to the work done by a water wheel due to a waterfall (chute d'eau).