Momentum vs Velocity
Momentum thiab nrawm yog ob lub ntsiab lus yooj yim heev. Ob lub tswv yim no muaj qhov zoo sib xws, tab sis hauv txoj kev xav, cov no yog ob qhov sib txawv. Nws yog ib qho tseem ceeb kom muaj kev nkag siab meej nyob rau hauv ob qho tib si nrawm thiab lub zog kom ua tau zoo hauv cov haujlwm xws li mechanics, automobile engineering, thiab yuav luag txhua qhov haujlwm hauv physics thiab engineering. Kab lus no yuav nthuav qhia cov ntsiab lus ntawm ob lub ntsiab lus, lawv siv, cov kev cai lij choj thiab kev xav txog lawv, lawv qhov zoo sib xws thiab thaum kawg lawv qhov sib txawv.
Kev nrawm
Veocity yog lub cev muaj nuj nqis ntawm lub cev. Lub nrawm nrawm tuaj yeem muab tau raws li qhov nrawm nrawm ntawm cov khoom nrog cov kev taw qhia cov khoom txav mus rau lub sijhawm ntawd. Hauv Newtonian mechanics, qhov nrawm yog txhais raws li tus nqi ntawm kev hloov pauv. Ob qhov kev tshaj tawm thiab kev hloov pauv yog vectors. Lawv muaj tus nqi ntau thiab muaj kev taw qhia. Tus nqi ntau ib leeg ntawm kev tshaj tawm hu ua modulus of velocity. Qhov no yog sib npaug rau qhov ceev ntawm qhov khoom. Qhov nruab nrab tshaj tawm ntawm ib qho khoom yog qhov sib txawv ntawm qhov kawg thiab qhov pib tshaj tawm (hauv peb qhov sib cais) faib los ntawm tag nrho lub sijhawm. Qhov ceev ntawm ib yam khoom yog ncaj qha ntsig txog lub zog kinetic ntawm cov khoom. Siv classical mechanics lub kinetic zog ntawm ib yam khoom yog ib nrab lub sij hawm loj multiplied los ntawm tshaj tawm squared faib. Txoj kev xav ntawm kev sib raug zoo qhia tau hais tias muaj ntau dua version, uas tsis tau tham txog ntawm no. Txoj kev xav ntawm kev sib raug zoo kuj qhia tau hais tias qhov pom qhov loj ntawm ib yam khoom nce thaum qhov nrawm ntawm qhov khoom nce. Qhov nrawm ntawm ib qho khoom tsuas yog nyob ntawm qhov kev hloov pauv ntawm lub sijhawm sib koom ua ke ntawm qhov khoom.
Nyob zoo ib tsoom phooj ywg sawv daws
Momentum yog ib qho tseem ceeb heev ntawm cov khoom txav. Lub zog ntawm ib yam khoom yog sib npaug rau qhov loj ntawm cov khoom sib npaug los ntawm qhov nrawm ntawm qhov khoom. Txij li thaum huab hwm coj yog ib tug scalar, lub momentum yog ib tug vector, uas muaj tib yam kev taw qhia raws li qhov tshaj tawm. Ib txoj cai tseem ceeb tshaj plaws hais txog lub zog yog Newton txoj cai thib ob ntawm kev txav chaw. Nws hais tias lub zog net ua rau ntawm ib qho khoom sib npaug rau qhov kev hloov pauv ntawm lub zog. Txij li thaum huab hwm coj tsis tas li, ntawm cov tshuab tsis sib xws, qhov kev hloov pauv ntawm lub zog yog sib npaug rau huab hwm coj los ntawm kev nrawm ntawm cov khoom. Qhov tseem ceeb tshaj plaws los ntawm txoj cai no yog lub zog txuag txoj kev xav. Qhov no hais tias yog tias lub zog ntawm lub kaw lus yog xoom tag nrho lub zog ntawm lub system tseem nyob tas li. Momentum yog khaws cia txawm nyob rau hauv relativistic nplai. Nws yuav tsum raug sau tseg tias lub zog yog nyob ntawm ob qhov loj ntawm cov khoom thiab lub sijhawm lub sijhawm sib koom ua ke hloov pauv ntawm cov khoom.
Qhov txawv ntawm lub zog thiab nrawm yog dab tsi?
• Momentum yog nyob ntawm huab hwm coj, thiab qhov nrawm yog ywj siab ntawm pawg.
• Lub zog yog khaws cia hauv qhov kaw, tab sis qhov nrawm tsis tau khaws cia.
• Ib qho kev quab yuam sab nraud ib txwm yuav tsum hloov qhov nrawm, tab sis lub zog tuaj yeem hloov pauv los ntawm kev hloov huab cua.
