Esinye sezimpawu ezibalulekile zento ubuningi, okubizwa nangokuthi ukuminyananya. Igama elipholile yi-density. Ubuningi buyisilinganiso sobuningi nomthamo wento ethile. Ngokwezibalo, kubhaliwe:
ρ = m/V
(ρ funda “rho”) uhlamvu lwesiGreki oluvame ukusetshenziswa ukuveza ubuningi, u-m uwubunzima kanti u-V uwuvolumu.
Uhlelo lwamayunithi lwamazwe ngamazwe ukuminyana amakhilogremu ngemitha eyi-cubic (kg/m2)3). Kumayunithi e-CGS, okungukuthi amasentimitha, amagremu, namasekhondi, iyunithi yobuningi ivezwa ngamagremu ngesentimitha ngayinye (gr/cm3).
Okulandelayo idatha yobuningi bezinto eziningana.
Ubuningi bento eshiwo kuthebula elingenhla bubukhulu bento ekushiseni okungu-0o C kanye nokucindezela kwe-atm eyi-1 (atm = iyunithi yokucindezela)
Ubuningi bomoya noketshezi
Ubuningi boketshezi buhlukile kobuningi bento eqinile. Insimbi noma ukhuni lunobuningi obufanayo kuzo zonke izingxenye. Lokhu kuhlukile koketshezi, njengomoya noma amanzi. Uma umoya uphakeme ngaphezu kolwandle, ubuningi bawo buyancipha. Lokhu kungenxa yokuthi amandla adonsela phansi ayancipha ngokuphakama. Uma ukhuphuka, amandla adonsela phansi ayancipha, ngakho-ke inani lomoya odonswayo nalo liyancipha. Inani lomoya eduze kolwandle likhulu kunenani lomoya phezulu kwentaba. Esikhaleni noma kumthamo ofanayo, umoya eduze kolwandle unesisindo esikhulu ngakho-ke ubuningi obukhulu. Ngokuphambene nalokho, umoya phezulu kwentaba unesisindo esincane ngakho-ke ubuningi obuphansi. Uma uqhelelene nolwandle, ubuningi bomoya buphansi.
Kuthiwani ngobuningi bamanzi, isibonelo amanzi olwandle? Umoya wakhiwe ngama-athomu noma ama-molecule ahlukene, ahambayo, ngakho-ke inani lomoya lithonywa kakhulu amandla adonsela phansi adonsela kuwo. Ngokuphambene nalokho, ama-molecule amanzi awami wodwa futhi awahlukani; ahlanganiswa ndawonye futhi awashukumi kalula. Ngakho-ke, inani lama-molecule amanzi ebusweni bolwandle alihlukile kakhulu enanini lama-molecule amanzi phansi kolwandle. Ngakho-ke ubukhulu bamanzi olwandle ebusweni bucishe bufane nobukhulu bamanzi olwandle phansi kolwandle, yize ukuphakama kuhlukile.
Umphumela wokushintsha kwezinga lokushisa kanye nomthamo ekubuneni koketshezi
Into ngayinye iyakhula (umthamo uyanda) uma izinga lokushisa layo likhuphuka futhi lincipha (umthamo uyancipha) uma izinga lokushisa layo lehla. Ngaphandle kwamanzi ekushiseni okungu-0 o C–4 o C. Izibonelo ezilandelayo zichaza lokhu. Wake wabhekana nesigameko lapho isondo lesithuthuthu esipakwe lawela phansi yize kungekho ukuvuza? Isondo lesithuthuthu lawela phansi ngoba umthamo womoya ngaphakathi kwesondo wehlile. Umthamo womoya wehlile ngoba izinga lokushisa lomoya lehlile. Lokhu kwenzeka lapho izinga lokushisa lomoya libanda kakhulu. Esinye isibonelo. Sicela uqhumise ibhaluni lerabha lize likhule bese ubopha umlomo webhaluni ukuze umoya ungaphumi. Yomisa ibhaluni endaweni eshisayo. Qaphela ukuthi kwenzekani ebhaluni! Ibhaluni lizoqhuma ngoba umthamo womoya ngaphakathi kwebhaluni uyanda ngenxa yokwanda kwezinga lokushisa lomoya. Ukuqina kwerabha akukwazi ukumelana nokwanda komoya ngakho ibhaluni liyaqhuma.
Izibonelo ezimbili ezingenhla zibonisa ukuthi umthamo woketshezi, kungaba uketshezi noma igesi, ungashintsha uma izinga lokushisa lalo lishintsha. Ubuningi bomoya ngaphakathi kwesondo elivaliwe noma ibhaluni buhlala bunjalo; umthamo kuphela oshintshayo. Izinguquko kumthamo zibangela ukuthi ubuningi bomoya bushintshe.
