Tsab xov xwm hais txog qhov ceev thiab qhov hnyav tshwj xeeb
ceev
Ib qho tseem ceeb ntawm ib yam khoom yog qhov ceev. Qhov ceev yog qhov sib piv ntawm qhov hnyav rau qhov ntim. Sau ua lej:
ρ = m / V
ρ (rho) yog ib tsab ntawv Greek uas feem ntau siv los qhia qhov ceev, m yog qhov hnyav thiab V yog qhov ntim. Qhov ceev ntawm cov kua dej sib xyaw yog txawv ntawm qhov ceev ntawm cov khoom sib xyaw. Piv txwv li, hlau muaj qhov ceev tib yam hauv txhua qhov. Hauv lub ntiaj teb huab cua, qhov siab dua ntawm lub ntiaj teb saum npoo av, nws qhov ceev me dua, thaum rau dej hiav txwv, qhov tob dua ntawm dej hiav txwv, nws qhov ceev ntau dua. Qhov ceev ntawm cov kua dej sib xyaw tuaj yeem nyob ntawm cov yam ntxwv ib puag ncig xws li kub thiab siab.
Lub Chav Txheej Txheem Thoob Ntiaj Teb rau qhov ceev yog kilograms ib cubic meter (kg/m3 ) . Rau cov chav CGS, chav ntawm qhov ceev ntawm pawg yog qhia hauv grams ib cubic centimeter (gr/cm3 ) . Hauv qab no yog cov ntaub ntawv ceev ntawm ntau yam khoom.
Qhov ceev ntawm cov tshuaj uas tau hais hauv lub rooj saum toj no yog qhov ceev ntawm cov khoom siv ntawm 0 o C thiab siab ntawm 1 atm (cua, atm = chav ntawm siab).
Kev nqus tshwj xeeb
Qhov hnyav tshwj xeeb yog qhov sib piv ntawm qhov ceev ntawm ib yam khoom rau qhov ceev ntawm dej. Qhov hnyav tshwj xeeb ntawm ib yam khoom tuaj yeem tau los ntawm kev faib qhov ceev los ntawm 103 kg / m3 (103 kg / m3 = qhov ceev ntawm dej). Lub zog hnyav tshwj xeeb tsis muaj qhov ntev.
Yog tias qhov ceev ntawm ib yam khoom me dua qhov ceev ntawm dej, ces yam khoom ntawd yuav ntab. Qhov hnyav tshwj xeeb ntawm yam khoom ntab qis dua 1. Ntawm qhov tsis sib xws, yog tias qhov ceev ntawm ib yam khoom siab dua qhov ceev ntawm dej, qhov hnyav tshwj xeeb yuav siab dua 1. Hauv qhov no, yam khoom ntawd yuav tog.
