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School In case the maximum output (100%), all the heat absorbed from the hot reservoir would be turned into work and heat rejection to zero would be cold source (Q But that the efficiency of a heat engine is 100%, it can not lose energy through friction between parts, viscosity, or any force that produces heat. But you've probably noticed that the carcass of an air conditioner heats, then in that case, this condition is not satisfied. How to resolve this problem of income, without forgetting the question of reversibility of the process or not? Based on the ideas of Carnot, Clausius associated with the work done by machines with the thermal difference between the Motive Power of the hot source (P ) and the cold source (P For this power it was given by the product of a magnitude which called entropy (S), the temperature as in Equation (4). W = S Comparing equations (4) and (1), you may notice that they will be equal only if the entropy is the ratio of the heat exchanged and temperature: You must be wondering, "But what advantage we have with that?" With this formulation, Clausius found that if a process is reversible or has a machine yield of 100%, the entropy of the system is preserved. If, on the other hand, the system is not reversible, or if a machine does not have 100% yield, increases the entropy of the system (S> 0). Thus, the Second Law of Thermodynamics can be written in terms of the entropy of the system: "In any case, the entropy of the universe never decreases." DEBATE In the case of coal being burned to ashes, it would be possible to decrease the entropy spontaneously? How? What kind of process occurs with coal and that has to do with the decrease or increase of entropy? You must be curious, after all, what is all this about entropy? For now, let'sthink of it only as a parameter used to describe the reversibility or not a process, but physically the message entropy is even more important. Be sure to read Chapter 7 (Verse and Reverse - The order of the universe), where that greatness will receive a more thorough treatment. Thermodynamics
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Škola U slučaju maksimalni izlaz (100%), a sve se toplina apsorbira iz spremnika tople bi se pretvorio u posao i odbijaju vrućinu nulu će biti hladno Izvor (Qf No, da je učinkovitost topline motora je 100%, to se ne može izgubiti energiju putem trenja između dijelova, viskoznost, ili bilo sila koja proizvodi toplinu. No, vjerojatno ste primijetili da je truplo klima uređaj zagrijava, onda u tom slučaju, ovaj uvjet nije ispunjen. Kako bi riješili taj problem prihoda, ne zaboravljajući pitanje o reverzibilnosti procesa ili ne? Temelji se na ideji Carnot, Clausius povezanih s radom prema strojevima s termalnom razlika između Motivacijska snaga vrućeg izvora (Pq) i hladnog izvora (Pf). Za ovu vlast je dao produktom magnitude koja se naziva entropija (S), temperatura, kao u jednadžbi (4). W = Sq q T -F T Sf Uspoređujući jednadžbe (4) i (1), možda ćete primijetiti da su oni će biti jednaki samo ako je entropija je omjer topline razmijenjene i temperature:P S =T Morate se pitate: "A što mi imamo prednost s tim?" S ovom formulacijom, Clausius otkrili da ako proces je reverzibilan ili ima stroj prinos od 100%, entropija sustava je očuvana. Ako, s druge strane, sustav nije reverzibilna, ili ako stroj nema 100% prinosa, entropija se sustava povećava ( Dakle, Drugi zakon termodinamike može biti napisan u smislu entropije sustava: "U svakom slučaju, entropija svemira nikad ne smanjuje." DEBATA U slučaju ugljena izgara u pepeo, to bi bilo moguće smanjenje entropije spontano? Kako? Kakav proces događa s ugljenom i da ima veze sa smanjenje ili povećanje entropije? Morate biti znatiželjan, nakon svega, što je sve ovo o entropiji? Za sada, neka je samorazmišljati o njemu kao parametar koji se koristi za opisivanje reverzibilnosti ili ne proces, ali fizički je poruka entropija je još važnija. Budite sigurni da pročitate poglavlje 7 (Stih i obrnutog - Redoslijed svemiru), gdje je veličina dobit će temeljitije liječenje. Termodinamika