tailieunhanh - Muller A History of Thermodynamics The Doctrine of Energy and Entropy phần 2

Tham khảo tài liệu 'muller a history of thermodynamics the doctrine of energy and entropy phần 2', ngoại ngữ, ngữ pháp tiếng anh phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Hermann Ludwig Ferdinand von Helmholtz 1821-1894 25 turn a wheel say and still come back to the original position in order to begin a new cycle. These attempts had always failed and people came to the conclusion that a perpetuum mobile was impossible. Therefore as early as 1775 the Paris Academy decided not to review new propositions anymore. The conservation of mechanical energy - kinetic energy gravitational potential energy and elastic energywasfirmly believenlin. no matter how complex the arrangement of masses and springs and wheels was cf. Fig. . This could nmt be proved of comse since Total ggnsiblt arrangements couihbn irkeL nor couldfheeqeatifnsvfmstifn bessived for complex arranntminfg. Fig. . Design of a perpetuum mobile by Ulrich von Cranach. 1664 A perpetuum mobile was a proposition of mechanics. To be sure friction and inelastic collisions were recognized as counterproductive because they absorb work and annihilate kinetic energy - both produce heat. Helmholtz conceived the idea that .what has been called . heatisfirsttytlrs .life force Idnotic entrgyi of the thermal motion of the atoms and secondly the elastic forces between the atoms. The first is what was hitherto called free heat and the second is the latent heat So far that iden had teen expressed before h more id k sr bleadv - bin now came Helmhahnk firiTc ii s The bnvnsmg of ode aliimr and lgo attractions helwetc iliac jutt madea ndviliaciea opsObm more complex than any macroscopic sytSemhadnver leeeiiitt so uf lire inipessibilityof a 43 And some of those machines were complicated see Fig. . 26 2 Energy perpetuum mobile should still prevail. Just like energy was conserved in a complex macroscopic arrangement without friction and inelastic collisions so energy is still conserved - even with friction and inelastic collisions - if the motion of the atoms and the potential energy of their interaction forces is taken into account. Friction and inelastic collisions only serve to .