Bulk Modulus vs Young Modulus
Txhua yam khoom / khoom yog tsim los ntawm atoms. Hom atoms, tus lej thiab lawv cov kev sib txuas sib txawv ntawm cov khoom siv rau cov khoom siv, thiab uas txhais tau tias txhua yam ntawm lawv cov yam ntxwv tshwj xeeb. Txawm hais tias ntau npaum li cas atoms sib sau ua ke los tsim ib yam khoom, atoms tsis zoo li npaj rau hauv txoj kev compact uas tsis muaj qhov chaw nruab nrab ntawm lawv. Lub attraction thiab repulsion rog ntawm cov atoms, ib txwm khaws ib qho chaw nruab nrab ntawm lawv. Yog li ntawd, nyob rau hauv tej yam khoom, tsis muaj teeb meem npaum li cas lawv yog compact, muaj txaus thiab ntau qhov chaw ntawm lub atoms. Peb faib cov khoom tseem ceeb rau hauv peb chav kawm ua khoom, kua thiab roj. Lawv cov kev npaj atomic txawv. Cov khoom muaj ib qho kev sib cog lus atomic heev thaum, hauv cov pa roj, cov atoms tau tawg mus rau hauv lub ntim loj dua nrog kev sib cuam tshuam tsawg heev. Hauv cov kua, ib theem nruab nrab ntawm cov khib nyiab thiab roj tuaj yeem pom.
Bulk Modulus
Feem ntau cov tshuaj txo nws cov ntim thaum raug rau ib qho kev sib xws, sab nraud siv siab. Txawm li cas los xij, qhov kev txo qis no tsis yog ib txoj kab nkhaus, es, raws li qhov siab nce, qhov ntim txo exponentially. Bulk modulus hais txog qhov sib txuam ntawm compressibility los yog, nyob rau hauv lwm yam lus, nws yog ib qho kev ntsuas ntawm tsis kam mus compressibility. Ntxiv mus, nws piav txog cov khoom elastic ntawm ib yam khoom.
Bulk modulus tuaj yeem txhais tau tias qhov nce siab xav tau los txo qhov ntim los ntawm qhov tseem ceeb ntawm 1 / e. Thaum cov khoom raug compressed, nws yuav ua rau me ntsis resistant rau compression nyob ntawm seb lub atomic kev npaj nws muaj. Bulk modulus qhia qhov kev tiv thaiv ntawm ib yam khoom thaum compression tsis sib xws. Nws ntsuas hauv Pascal / bar lossis lwm chav ntsuas siab. Bulk modulus muab lub tswv yim ntawm kev hloov pauv hauv ntim ntawm cov khoom siv thaum lub siab ntawm nws hloov. Raws li rau cov khoom, bulk modulus yog ib yam khoom ntawm cov kua ib yam nkaus, nws qhia tau hais tias lub compressibility ntawm cov kua. Cov kua compressible ncaj ncees muaj cov qauv qis qis thiab cov kua compressible me ntsis muaj cov khoom siv siab. Hauv qab no yog qhov sib npaug los xam cov khoom siv ntau K.
K=-V(∂P/∂V)
V yog qhov ntim ntawm cov khoom thiab P yog lub siab thov.
Cov qauv ntawm cov hlau ntau yog 1.6 × 1011 P, thiab qhov no yog peb zaug tus nqi rau iav. Yog li ntawd, iav yog compressible peb zaug dua cov hlau.
Young Modulus
Cov tub ntxhais hluas modulus piav qhia txog cov khoom elastic ntawm ib yam khoom uas raug compression lossis ncab hauv ib qho kev taw qhia xwb. Piv txwv li, thaum ib tug hlau pas nrig yog stretched los yog compressed los ntawm ib sab, nws muaj peev xwm rov qab mus rau nws qhov qub ntev (los yog ze rau qhov ntawd). Qhov no qhia tau hais tias nyob deb npaum li cas cov hlau tuaj yeem tiv taus qhov nro lossis compression. Cov tub ntxhais hluas modulus yog qhov ntsuas ntawm no elastic khoom ntawm ib yam khoom. Cov tub ntxhais hluas modulus tau muaj npe tom qab tus kws kho mob Thomas Young. Qhov no tseem hu ua modulus ntawm elasticity. Cov tub ntxhais hluas modulus kuj tseem muaj cov chav nyob ntawm lub siab ua cov khoom siv ntau. Young modulus, E yog xam raws li qhia hauv qab no.
E=tensile stress/tensile strain
Qhov txawv ntawm Bulk Modulus thiab Young Modulus yog dab tsi?
• Bulk modulus yog txhais rau qhov sib txawv compression qhov twg lub siab siv los ntawm txhua qhov kev taw qhia uniformly. Cov tub ntxhais hluas modulus txhais tau tias tsuas yog rau ib qho axis ntawm cov khoom.
• Bulk modulus ntsuas qhov kev hloov pauv hauv ntim thaum siv lub siab, thiab Young modulus ntsuas qhov hloov pauv ntev.
• Nyob rau hauv cov qauv modulus ntau npaum li cas ntawm lub siab siv yog ntsuas. Hauv Young modulus siv tensile stress (compression lossis stretch) yog ntsuas.
