Qhov ceev ntawm lub suab yog qhov kev nthuav tawm ceev ntawm lub zog tsis muaj zog cuam tshuam hauv nruab nrab, thiab nws qhov loj me txawv raws li qhov xwm txheej thiab lub xeev ntawm qhov nruab nrab. Qhov ceev ntawm lub suab hauv huab cua yog li 340 m / s ntawm 1 tus qauv atmospheric siab thiab 15 ° C.

 

Kev nthuav tawm ceev ntawm lub suab yoj hauv nruab nrab elastic yog suab nrawm, nws lub cim yog c, chav tsev yog m / s: c = λf

Hauv cov qauv, f yog qhov vibration zaus, uas yog, tus naj npawb ntawm kev vibrations ib ob, Hz: λ yog lub wavelength, m.

 

Vim tias tsis muaj shear elasticity nyob rau hauv cov roj, tsuas yog ntim elasticity, yog li cov propagation daim ntawv ntawm cov roj tsuas yog longitudinal tsis. Hauv lwm lo lus, nyob rau hauv kev cuam tshuam ntawm lub suab tsis zoo, cov khoom hauv cov pa nruab nrab vibrate nyob ze ntawm lawv txoj haujlwm sib npaug, tsim cov txheej txheem sib kis thiab sib kis. Nyob rau tib lub sijhawm, kev txav mus los ntawm cov particle yog tib yam li kev nthuav tawm ntawm nthwv dej. Feem ntau, lub suab nrov tshaj tawm ntawm cov pa roj hauv txhua qhov xwm txheej yog qhov nyuaj heev. Nws cov lus qhia muaj feem xyuam nrog cov txheeb ze molecular loj, lub peev xwm kub tshwj xeeb, thiab cov khoom vaj khoom tsev sib npaug ntawm cov roj, thiab yuav tsis qhia ntawm no. Feem ntau cov teeb meem, lub suab nrov tshaj tawm qauv ntawm cov roj zoo tagnrho feem ntau yog siv.

 

Nws tuaj yeem ua pov thawj tias lub suab nrawm hauv cov roj zoo tagnrho yog: c = (rp / p) 0.5 Hauv cov qauv, r adiabatic coefficient yog sib npaug rau qhov sib piv ntawm qhov muaj peev xwm kub ntawm qhov siab mus tas li rau lub peev xwm kub ntawm qhov siab; p yog gas siab, Pa; ρ yog qhov ceev, kg / m3.

 

Kev nthuav tawm ceev hauv cov xov xwm sib txawv

Nqus 0m / s (uas yog, nws tsis tuaj yeem kis tau);

Cua (15 ℃) 340 m / s;

Cua (25 ℃) 346 m / s;

Cork 500m / s;

Kerosene (25 ℃) 1324 m / s;

Distilled dej (25 ℃) 1497 m / s;

Dej hiav txwv (25 ℃) 1531 m / s;

Copper (qws) 3750m / s;

Marble 3810m / s;

Aluminium (qws) 5000m / s;

Hlau (qws) 5200m / s;