Izinto: Incazelo yokushisa, ukuqhuba ukushisa, umthamo wokushisa
Wake waphuza itiye elibandayo, ubisi olubandayo, isiraphu ebandayo, njll.? Nokho, lapho senza itiye elibandayo, sivame ukuxuba amanzi ashisayo noma afudumele engilazini enama-cubes eqhwa. Amanzi ashisayo noma amanzi afudumele anezinga lokushisa eliphakeme, kuyilapho ama-cubes eqhwa enezinga lokushisa eliphansi. Ngemva kokuthinta isikhashana, ingxube yama-cubes eqhwa netiye elishisayo iphenduka itiye elibandayo (ingxube yama-cubes eqhwa netiye elifudumele ifinyelele izinga lokushisa elifanayo). Inqubo efanayo iyenzeka lapho sihlanganisa amanzi ashisayo namanzi abandayo. Ngemva kokuthinta, amanzi ashisayo namanzi abandayo aphenduka amanzi afudumele (ingxube yamanzi ashisayo namanzi abandayo ifinyelele izinga lokushisa elifanayo). Kungani lezi zinto zingafinyelela izinga lokushisa elifanayo ngemva kokuthinta?
Incazelo Yokushisa
Uma izinto ezinamazinga okushisa ahlukene zihlangana, ukudluliselwa kokushisa, okuvame ukubizwa ngokuthi ukushisa, kwenzeka kusukela entweni enezinga lokushisa eliphezulu kuya entweni enezinga lokushisa eliphansi. Lokhu kudluliselwa kokushisa kuyama uma izinto ezixhumene nazo zifinyelela izinga lokushisa elifanayo. Isibonelo, uma sixuba amanzi ashisayo namanzi abandayo, ukushisa kuvame ukuhamba kusuka emanzini ashisayo kuya emanzini abandayo. Uma sifaka insimbi eshisayo emanzini abandayo, ukushisa kuyahamba kusuka ensimbini eshisayo kuya emanzini. Ukugeleza kokushisa kuyama uma insimbi namanzi kufinyelela izinga lokushisa elifanayo. Lapho udokotela noma umhlengikazi enamathisela i-thermometer emzimbeni wakho, ukushisa kuyahamba kusuka emzimbeni wakho kuya ku-thermometer. Lokhu kudluliselwa kokushisa kuyama uma umzimba wakho ne-thermometer sekufinyelele izinga lokushisa elifanayo. Uma i-thermometer esetshenziswayo iyi-thermometer ye-mercury, lapho umzimba wakho ne-thermometer kufinyelela izinga lokushisa elifanayo, ubuso be-mercury buyayeka ukuhamba. Inombolo ekhonjisiwe ebusweni be-mercury izinga lokushisa lomzimba wakho ngaleso sikhathi.
Ngokwemvelo, ukushisa ngokwemvelo kuhamba kusuka ezintweni ezinokushisa okuphezulu kuya ezintweni ezinokushisa okuphansi. Ukudluliselwa kokushisa kuvame ukulinganisa amazinga okushisa ezinto ezithintana. Ngekhulu le-18, izazi zefiziksi zazisola ukuthi ukugeleza kokushisa kwakuwukuhamba koketshezi, uhlobo olungabonakali loketshezi (uketshezi luyizinto ezingageleza. Uketshezi luhlanganisa uketshezi namagesi. Amanzi (uketshezi) luketshezi ngoba lungageleza. Umoya nawo uketshezi ngoba lungageleza). Lolu ketshezi lwaqanjwa ngokuthi i-caloric . Ithiyori ye- caloric ayisasetshenziswa ngoba ngokusekelwe emiphumeleni yokuhlola, ukuba khona kwale caloric akunakufakazelwa.
Ngekhulu le-19, isazi sesayensi yezinkanyezi saseNgilandi okuthiwa uJames Prescott Joule (1818-1889) safunda indlela yokushisa amanzi esitsheni sisebenzisa isondo lokuvuselela. Ngokusekelwe emiphumeleni yocwaningo lwakhe, uJoule wenza ukuqhathanisa namanzi ashiswa ngomlilo. Lapho ilangabi nesitsha esinamanzi kuhlangana, ukushisa kuhamba kusuka emlilweni (izinga lokushisa eliphezulu) kuya emanzini (izinga lokushisa eliphansi). Ngemva kokuqhathanisa phakathi kokwanda kwezinga lokushisa lamanzi ngenxa yokuthintana nomlilo kanye nokwanda kwezinga lokushisa lamanzi ngenxa yomsebenzi owenziwe yi-stirrer, uJoule waphetha ngokuthi ukushisa kungamandla ahamba esuka entweni enokushisa okuphezulu aye entweni enokushisa okuphansi. Ukushisa akuwona amandla (ukushisa akulona uhlobo oluthile lwamandla, njengamandla e-kinetic, amandla angase abe khona, amandla amakhemikhali, njll.) . Ukushisa kungamandla ahamba ngenxa yokwehluka kwezinga lokushisa . Ngakho-ke lapho ukushisa kugeleza kusuka entweni enokushisa okuphezulu kuya entweni enokushisa okuphansi, amandla empeleni ahamba esuka entweni enokushisa okuphezulu aye entweni enokushisa okuphansi. Ukudluliselwa kwamandla kuyama uma izinto ezithintanayo zifinyelela izinga lokushisa elifanayo noma ukulingana kokushisa.
Ukuqhuba kwe-thermal
Kungani izitsha zokupheka eziningi zenziwe nge-aluminium? Ake sithi isandla sakho sobunxele siphethe insimbi, isandla sakho sokudla siphethe ingilazi, bese kuthintwa insimbi nengilazi emlilweni. Ingabe isandla sakho sobunxele noma kwesokudla yisona esizwa ukushisa ngokushesha? Le mibuzo, futhi mhlawumbe neminye oyoyibuza, ihlobene nokushisa kwento. Ukushisa kwento yikhono lento lokudlulisa ukushisa kuyo. Izinto ezine-thermal conductivity ephezulu (k) zingabaqondisi abahle bokushisa (abaqondisi abahle bokushisa). Ngokuphambene nalokho, izinto ezine-thermal conductivity ephansi zingabaqondisi ababi bokushisa (abaqondisi ababi bokushisa).
Amandla Okushisa
Umthamo wokushisa (C) inani lokushisa elidingekayo ukuphakamisa izinga lokushisa lento yonke ngezinga elilodwa. Ifomula yamandla okushisa yile:
C = mc
Ulwazi: C = umthamo wokushisa, m = isisindo sento, c = ukushisa okuthile kwento.
