October 11, 1889 (Year of the OX September 17), the British physicist Joule's death.

Joule's death "target =" _blank "> Joule was born December 24, 1818, the 19th century British physicist young hard self-study of the chemical and physical child, he did not attend school, the time spend all learn and experiment. later, Joule opportunity to meet then the chemist Dalton, he worship Dalton as a teacher, humbly ask for income the great.
in Joule young The motor was invented shortly Joule want to use the experimental determination of how effective this new machine, whether it is economically worthwhile, this thinking led to his great discovery later.
Joule life most of the time in the lab moderate off in 1840, the [L $ dj��.c��m] Joule done repeatedly energized conductor heating Experimental he energized resistive wire placed in water to determine the heat generated by the current, with the current intensity proportional to the square, with the conductor resistance is proportional to the proportional relationship with power, this rule is called Joule's law. (history today www.lssdjt.com)
on the basis of this finding, the Joule continue to explore various forms of exercise relationship between the number and conversion. 1843, Joule announced: nature, can not be destroyed, where the mechanical energy consumption, always get quite hot, the heat just a form of energy. announced at the time immediately sensational because it breaks the notion of a ruling years of the so-called heat and mass mechanical materialism said
1847 joules do so far is still considered to be the best experiment: he installed a water calorimeter the placement of the rotary shaft with blades in the middle, and then let the dropped weights drive blade rotates, due to the friction of the blade and water, water, and the amount of heat heats up the whereabouts of the height according to the weights, as well as within the calorimeter water elevated temperature, it can calculate the value of the equivalent of heat to
Joule whale oil instead of water for experiments, and were measured the average value of the equivalent of the thermal power of weight 428.9 kg m / kcal. followed with mercury instead of water, the continuous improvement of the experimental method, away from him until 1878, when this work for nearly 40 years, he has conducted over 400 experiments before and after the various ways in 1849, with the friction the results obtained by the method so that the water becomes hot Contact 1878 is the same, namely, 423.9 kg by weight of m / kcal. an important physical constant determination can be maintained for 30 years without making large corrections in Physics is extremely rare in the history of things. value at that time was recognized as the mechanical equivalent of heat value of J, it J than it is now recognized value: 427 kg weight m / kcal approximately 0.7% in the conditions at the time, can do such precise experiments, the Joule experiment very superb skills on the convening of the meeting of the Association of British Science in Oxford,
1847 joules promote their theory again, this indomitable experimental home, in the face of doubts and reproach, the firm claims that various forms of energy can be quantitatively mutual transformation. 1852, Joule and Kelvin cooperation, found the famous Tom Sun (ie open Seoul Man) - Joule effect. This is a gas pressure through a narrow hole expansion cooling effect, modern cryogenic engineering provides an effective cooling methods.
until 1850, from the different ways to different methods of energy conservation and conversion law many scientists have announced the same and Joule conclusion Joule made before they get everyone recognized. ($ dj��.c��m) became a member of the Royal Society in 1850 joules.
Joule died on October 11, 1889, and their descendants to commemorate He, in the International System of Units, the unit of work and energy as "Joule.