Kev nyuaj siab-txheej zog ntawm cov roj hmab
Qhov kev ntxhov siab-strain nkhaus yog ib yam ntawm cov roj hmab elongated crystalline, thiab nws cov khoom tseem ceeb yog qhov hloov pauv hloov pauv los ntawm qhov system tau txiav txim. Raws li cov molecule yog maj mam straightened, cov nyhuv cais ntawm cov ceg chains ntawm cov molecular saw ploj, thiab cov intermolecular attraction ua ib qho tseem ceeb, yog li pab tiv thaiv ntxiv deformation, yog li cov roj hmab yuav qhia siab tensile zog thaum tag nrho stretched. Qhov kev ntxhov siab ntawm roj hmab nyob rau hauv tas li strain yog qhov ua haujlwm ntawm qhov kub thiab txias. Cov roj hmab kev nyuaj siab yuav nce proportionally nrog qhov nce ntawm qhov kub thiab txias. Qhov kev cia siab ntawm roj hmab kev ntxhov siab ntawm qhov kub thiab txias yog hu ua Joule effect thiab qhia txog qhov sib txawv ntawm qhov elasticity ntawm hlau thiab roj hmab. Nyob rau hauv cov hlau, txhua lub atom yog tuav nyob rau hauv ib tug nruj lattice los ntawm interatomic rog, thiab kev ua hauj lwm ua rau deform cov hlau yog siv los hloov qhov kev ncua deb ntawm lub atoms, ua rau ib tug hloov nyob rau hauv lub zog sab hauv. Yog li ntawd, nws elasticity yog hu ua "zog elasticity", thiab nws elastic deformation ntau npaum li cas me dua li ntawm "entropy elasticity" nyob rau hauv roj hmab, uas yog feem ntau yog vim qhov kev hloov ntawm entropy nyob rau hauv lub system. Hauv kev siv dav dav, qhov kev ntxhov siab-txoj kev nkhaus ntawm cov roj hmab yog nonlinear, yog li tus cwj pwm elastic ntawm cov roj hmab tsis tuaj yeem txiav txim siab los ntawm Young's modulus.
