Izinto eziningi eziqinile zithola ukwanda okuqondile lapho izinga lokushisa lishintsha. Ukwanda okuqondile ubude bento buyanda noma ubude bento buyancipha. Ngokuvamile, ubude bento buyanda lapho izinga lokushisa likhuphuka, kanti ubude bento buyancipha lapho izinga lokushisa lehla. Ungase ucabange ukuthi ukwanda okuqondile kungenzeka kuphela ezintweni ezifana nezintambo ezincane. Isibonelo, bheka imoto epakwe eceleni komgwaqo, ukuze ivezwe elangeni. Lapho imoto ishisa kakhulu, ipuleti lensimbi lingakhula, noma ubude obuseceleni bungakhula. Uphahla lwezindlu ezenziwe nge-zinc nalo lungakhula. Kulokhu, lapho i-zinc ishisa kakhulu, imiphetho ye-zinc iyanda ububanzi futhi i-zinc ingakhula ngisho nobukhulu. Into efanayo yenzeka emizileni yesitimela kanye nensimbi noma insimbi ebhulohweni.
Izinto eziningi eziqinile ziyanda noma zinciphe lapho izinga lokushisa lento lishintsha, ngakho-ke sidinga ukwazi ukuthi ukushintsha kwezinga lokushisa kuthinta kanjani ukwanda kwezinto eziqinile. Isibonelo, igebe emizileni yesitimela. Imizila yesitimela yenziwe ngensimbi. Onjiniyela babebale ububanzi begebe phakathi kwesitimela ngasinye. Ngosuku olushisayo, isitimela sizokhula ngamasentimitha ambalwa. Uma sidlula isitimela, izinga lokushisa lesitimela nalo liyakhuphuka ukuze isitimela sidlule ngamasentimitha amangaki. Ngobusuku obubandayo, isitimela sincipha sibe ngamasentimitha amangaki.
Ngokusekelwe emiphumeleni yokuhlaziywa, onjiniyela balinganisa ibanga eliphakathi kwezikhala zesitimela, ukuze lapho izinga lokushisa lesitimela likhuphuka, iziteshi zingathintani futhi zigobe.
Ukuze usisize sithole ifomula echaza ubudlelwano phakathi kokushintsha kwezinga lokushisa kanye nobukhulu bokwanda kobude, bukeza into eqinile ekhula, njengoba kuboniswe esithombeni esingezansi.
To = izinga lokushisa lokuqala, T = izinga lokushisa lokugcina, Lo = ubude bokuqala, ΔL = ushintsho lobude, L = ubude ngemva kokunwetshwa, ΔT = ushintsho lokushisa.
Uma izinga lokushisa lento = Ku- o (into isabanda), ubude bento = Lo o . Uma izinga lokushisa lento = T (izinga lokushisa lento liyakhula), ubude bento = L.
Ngokusekelwe emiphumeleni yokubuka nokuhlola, izinguquko ebudeni bento ziyalingana noshintsho emazingeni okushisa. Uma izinga lokushisa likhuphuka, ubude bento buyakhuphuka. Ngokuphambene nalokho, lapho izinga lokushisa liyancipha, ubude bento buyancipha. Ushintsho ebudeni bento luphinde lulingane nobude bento yokuqala (Lo). Uma izinguquko zokushisa zifana, izinto ezingamamitha ayi-10 ubude, isibonelo, zizophindwa kabili ngobude uma kuqhathaniswa nezinto ezingamamitha ama-5 ubude. Ngakho-ke, uma into ide, kulapho into ikhula khona.
Izinguquko kubude bento (L) zihambisana nezinguquko kuzinga lokushisa (ΔT): ΔL α ΔT
Izinguquko kubude bento (ΔL) zilingana nobude bento yokuqala (L o ): ΔL α L o
Izinguquko kubude bento ngayinye ziyahlukahluka. Nakuba izinguquko zokushisa zifana, ukwanda okubonwa yinsimbi akufani nengilazi. Ngokufanayo nakwezinye izinto. Ngakho-ke, ukwanda okuqondile kuncike ku-coefficient yokwanda okuqondile kwento ngayinye. Uma i-coefficient yokwanda okuqondile inkulu, ubude buyanda kakhulu. Uma i-coefficient yokwanda okuqondile incane, ubude buyanda kancane. Kungashiwo ukuthi ushintsho kubude bento luhambisana ne-coefficient yokwanda okuqondile.
∆ L ∝ α
Ukuqhathanisa okuthathu okungenhla kuvezwa ku-equation:
Incazelo: ΔL = Ushintsho lobude, α = I-coefficient yokwanda okuqondile (amayunithi α = K -1 noma (Co ) -1 , L o = Ubude bokuqala, ΔT (T 1 – To ) ΔT = Ushintsho lokushisa (izinga lokushisa lokugcina – izinga lokushisa lokuqala)
Ubude obuphelele bento ngemva kokubhekana nokwanda noma ukuncishiswa bungatholakala ngokungeza ubude bokuqala bento (Lo o ) kanye noshintsho lobude bento (ΔL).
Incazelo: ΔL = ubude bento ngemva kokunwebeka noma ukuncipha, Lo = Ubude bokuqala bento, ΔL = L – Lo = Ushintsho lobude, α = I-coefficient yokwanda okuqondile (amayunithi ka-α = K-1 noma (Co)-1, ΔT = T – To = Ukushintsha kwezinga lokushisa, To = Izinga lokushisa lokuqala, T = izinga lokushisa lokugcina.
Uma ushintsho lokushisa (TT o ) luyi-negative, khona-ke ushintsho lobude (LL o ) nalo luyi-negative.
Kulokhu, ubude bento buyancipha. Ngokuphambene nalokho, uma ushintsho lokushisa (TT o ) luhle, khona-ke ushintsho lobude (LL o ) nalo luhle. Kulokhu, izinto ziyanda ngobude.
Okulandelayo inani le-coefficient yokwanda okuqondile kwezinto eziqinile, ekushiseni okungu-20 °C. Ukuma kwezinto eziwuketshezi kanye negesi kuyashintsha ukuze lezi zinhlobo ezimbili zezinto zingabi nakho ukwanda okuqondile. I-coefficient yokwanda okuqondile kwento eqinile nayo incike ekushiseni. Emazingeni okushisa ahlukene, i-coefficient yokwanda okuqondile kwezinto eziqinile nayo iyahlukahluka. Uma umehluko wokushisa ungabaluleki kakhulu, umehluko ku-coefficient yokwanda okuqondile awubalulekile kakhulu kangangokuthi unganganakwa.
