Maitiro eThermodynamic
Kupisa (Q) isimba rinofamba kubva pane chimwe chinhu kuenda kune chimwe nekuda kwekusiyana kwekupisa. Nezve masisitimu nenzvimbo, kupisa isimba rinofamba kubva pane sisitimu kuenda kune imwe kana simba richifamba kubva pane nharaunda kuenda kune imwe, nekuda kwekusiyana kwekupisa. Kana tembiricha yesisitimu yakakwira kupfuura tembiricha yeambient, kupisa kuchayerera kubva pane sisitimu kuenda kune imwe nzvimbo. Kana tembiricha yeambient yakakwira kupfuura tembiricha yesisitimu, saka kupisa kunoyerera kubva pane nharaunda kuenda kune imwe.
Kupisa (Q) isimba rinofamba nekuda kwekusiyana kwetembiricha, nepo basa (W) rine chekuita nekufambiswa kwesimba kuburikidza nebasa. Semuenzaniso, kana sisitimu ikashanda pane nharaunda, simba rinofamba kubva pane sisitimu kuenda kune nharaunda. Kusiyana neizvi, kana nharaunda ikashanda pane sisitimu, simba rinofamba kubva pane nharaunda kuenda kune imwe sisitimu.
Simba remukati uye mutemo wekutanga wethermodynamics
Simba remukati (U) remuchina uyu ndiro huwandu hwesimba rese remamorekuru muchina uyu, pamwe nehuwandu hwesimba rese rinobva mukudyidzana kwemamorekuru muchina uyu. Kana kupisa kukayerera kubva kunharaunda kuenda kuchina uyu (muchina uyu unogamuchira simba), simba riri muchina uyu rinowedzera. Kusiyana neizvi, kana muchina uyu ukashanda panharaunda (muchina uyu unoburitsa simba), simba riri muchina uyu rinoderera.
Zvichibva pakuchengetedzwa kwesimba, shanduko dzesimba remukati mehurongwa = kupisa kunowedzerwa muhurongwa (hurongwa hunogamuchira simba) kunze kwebasa rinoitwa nehurongwa (hurongwa hunoburitsa simba).
Δ U = shanduko dzesimba remukati, Q = Kupisa, W = Basa
Simba remukati isimba risingaonekwe zvakanyanya remuchina zvekuti kukosha kwawo hakugone kuzivikanwa. Kunyange hazvo shanduko musimba remukati dzichigona kuzivikanwa kuburikidza nesimba rinowedzerwa kuhurongwa uye simba rinoburitswa nehurongwa muchimiro chekupisa nebasa. Kusiyana neizvi, huwandu hukuru hwakadai setembiricha (T), kumanikidzwa (p), vhoriyamu (V) uye huremu (m) kana mamwe mamoles (n), hunozivikanwa.
Kupisa nebasa zvinongobatanidzwa chete mukutamiswa kwesimba pakati pesisitimu nenzvimbo. Kupisa nebasa hazvisi huwandu hunoratidza mamiriro esisitimu.
Saina mitemo yekupisa (Q) uye basa (W)
Mitemo yechiratidzo cheKupisa neKushanda inogadziriswa zvichienderana ne equation yeMutemo wekutanga weThermodynamics. Kupisa (Q) mu equation iri pamusoro apa ndiko kupisa kunowedzerwa ku system (Q positive), nepo basa (W) mu equation iri pamusoro apa riri basa rinoitwa ne system (W positive). Kana kupisa kukabuda mu system, saka Q ndere negative. Kana basa rikaitwa pa system, saka W ndere negative.
Muenzaniso 1:
Kana kupisa 2000 Joules kukawedzerwa kusystem, nepo system ichishanda 1000 Joules. Simba remukati rinochinja zvakadii?
mhinduro
Δ U = Q – W = 2000 – 1000 = 1000 Joules.
Sisitimu iyi inotora maJoules maviri ekupisa (simba rinogashira sisitimu), sisitimu iyi inopawo maJoules zana ekushanda (simba rekuburitsa sisitimu). Kuchinja kwesimba resisitimu = maJoules zana.
Muenzaniso 2:
Kupisa maJoules 2000 kunobuda musystem. Sisitimu inoita basa re1000 Joules. Verenga shanduko dzesimba remukati mesystem.
mhinduro
Kana sisitimu ikaburitsa kupisa, zvinoreva kuti Q inenge iri negative.
Δ U = Q – W = -2000 – 1000= -3000 Joules.
Sisitimu iyi inoburitsa kupisa kwemaJoule 2000. Sisitimu iyi inoitawo basa remaJoule 1000 (simba rekuburitsa sisitimu). Saka, simba remukati mesisitimu rinoderedzwa ne3000 J.
Muenzaniso 3:
Kupisa kwemaJoules 2000 kunowedzerwa kusystem, uye basa remaJoules 1000 rinoitwa pasystem. Verenga shanduko dzesimba remukati mesystem.
mhinduro
Basa rakaitwa pasystem, saka W iri negative.
Δ U = Q – W = 2000 – (-1000) = 3000 Joules.
Simba remukati mehurongwa rinowedzera ne3000 Joules.
