Maphunziro Oyambira a Fiziki

Ngati tiyang'ana mosamala, utsi wochokera ku motowo ungawoneke poyamba. Patapita kanthawi, utsi sungawoneke. Kodi mwagwiritsa ntchito mafuta onunkhira? Ngakhale mukupaka mafuta onunkhira m'chipindamo, anthu ena omwe ali kunja kwa nyumba nawonso amatha kumva fungo la mafuta onunkhirawo. Ngati mayi akuphika chakudya chokoma komanso chokoma kukhitchini, fungo la kuphika likhozanso kumveka kuchokera kunyumba kwa mnansi. Chifukwa chiyani zili choncho?

Pali zitsanzo zina zambiri. Ngati muyika madontho ochepa a inki mu galasi lokhala ndi madzi oyera, inki, kapena utoto wa chakudya udzafalikira mofanana m'madzi onse. Izi zimachitika zokha. Zitsanzo zina zam'mbuyomu ndi zochitika zofalitsa zomwe nthawi zambiri zimachitika m'moyo watsiku ndi tsiku. Kufalitsa ndi njira yosuntha zinthu kuchokera ku kuchuluka kwakukulu kupita ku kuchuluka kochepa. Chimene chimatanthauza kuchuluka kwa mamolekyu/mamolekyu a chinthu pa voliyumu iliyonse. Malo okhala ndi kuchuluka kwakukulu ndi malo omwe pali mamolekyu ambiri a zinthu pa voliyumu iliyonse. Mosiyana ndi zimenezi, kuchuluka kochepa ndi malo omwe pali mamolekyu ochepa pa voliyumu iliyonse.

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Mphamvu mu mpweya wabwino kwambiri wa monatomic

Mphamvu yomwe ili mu mpweya wabwino wa monatomic ndi kuchuluka kwa mphamvu yonse ya kinetic yosinthika ya mamolekyulu abwino a mpweya wa monatomic. Kuchuluka kwa mphamvu yonse ya kinetic yosinthika ya mamolekyulu abwino a mpweya = chinthu chomwe chimachokera ku mphamvu yapakati ya kinetic yosinthika ya molekyulu iliyonse ndi kuchuluka kwa mamolekyu (N). Mwa masamu:

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Chiphunzitso cha mphamvu chogawa mphamvu chinachokera m'malingaliro ndi Clerk Maxwell pogwiritsa ntchito njira zowerengera. Chimatchedwa chiphunzitso chifukwa palibe umboni kudzera mu kuyesa. Kugawa mphamvu kumatanthauza kugawa mphamvu mofanana.

KE = mphamvu yapakati yosinthira ya mamolekyu a mpweya (Joule)

k = nthawi zonse ya Boltzmann = 1.38 x 10^-23 J/K

T = kutentha kwathunthu kwa molekyulu yoyenera ya mpweya (Kelvin)

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Kuwonjezera pa kupanikizika, chimodzi mwa zinthu zomwe zimasonyeza mtundu waukulu wa mpweya ndi kutentha (T). Equation ya kupanikizika kwa mpweya:

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Ndi kChiphunzitso cha kinetic chimati chinthu chilichonse chimakhala ndi maatomu kapena mamolekyulu ndipo kuti atomu kapena molekyulu imayenda mosalekeza mosasamala. Kuganiza kumeneku kwa chiphunzitso cha kinetic kumagwirizana ndi momwe atomu kapena molekyulu ilili ndi momwe mpweya ulili. Mphamvu ya kukoka pakati pa maatomu kapena mamolekyulu omwe amapanga mpweya ndi yofooka kotero kuti maatomu kapena mamolekyulu amatha kuyenda momasuka.

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Nkhani ya lamulo la Boyle, lamulo la Charles, lamulo la Gay-Lussac

Lamulo la Boyle

Robert Boyle (1627-1691) adachita zoyeserera kuti afufuze ubale wochuluka pakati pa kuthamanga kwa mpweya ndi kuchuluka. Kuyesera kumeneku kumachitika poika kuchuluka kwa mpweya mu chidebe chotsekedwa. Mpaka njira yabwino kwambiri, adapeza kuti ngati kutentha kwa mpweya kumakhala kokhazikika, ndiye kuti kuthamanga kwa mpweya kukakwera, kuchuluka kwa mpweya kumachepa. Momwemonso, kuthamanga kwa mpweya kukachepa, kuchuluka kwa mpweya kumawonjezeka. Kuthamanga kwa mpweya kumakhala kofanana ndi kuchuluka kwa mpweya. Ubalewu umadziwika kuti Lamulo la Boyle. Mwa masamu:

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Malamulo a gasi a Boyle, Charles law ndi Gay-Lussac sagwira ntchito pa mikhalidwe yonse ya gasi, kotero kusanthula kwathu kumakhala kovuta kwambiri. Chifukwa chake, tapereka chitsanzo chabwino cha gasi. Gasi wabwino sapezeka m'moyo watsiku ndi tsiku; gasi wabwino ndiye njira yabwino kwambiri yopezera kusanthula. Kukhalapo kwa lingaliro labwino la gasi ili kumatithandizanso kuwunikanso ubale womwe ulipo pakati pa malamulo atatu a gasi.

Ubale pakati pa kutentha, voliyumu, ndi kuthamanga kwa mpweya

Mwa kutchula malamulo atatu a mpweya omwe ali pamwambapa, titha kupeza ubale wofala pakati pa kutentha, kuchuluka, ndi kuthamanga kwa mpweya.

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Mawu enieni a lamulo lachiwiri la thermodynamics sangafotokoze za njira zonse zosasinthika, kotero tikufunika mawu onse. Mawu onsewa akuyembekezeka kufotokoza njira zonse zosasinthika zomwe zimachitika m'chilengedwe chonse. Mawu onse a lamulo lachiwiri la thermodynamics adapangidwa pakati pa zaka za m'ma 1800, kudzera mu kuchuluka kotchedwa entropy (S). Entropy idayambitsidwa koyamba ndi Clausius ndipo idapangidwa kuchokera ku Carnot cycle (injini ya caloric yoyenera). Malinga ndi Clausius, kusintha kwa entropy kumachitika ndi dongosolo, pamene dongosolo limalandira kutentha kowonjezera (Q) pa kutentha kosasintha, komwe kumaimiridwa ndi equation:

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Nkhani yokhudza magwiridwe antchito a makina ozizira

Makina oziziritsira ndi makina omwe amatenga kutentha kuchokera pamalo otentha pang'ono, kenako nkuwasamutsa kupita kumalo otentha kwambiri. Kuti izi zitheke, makinawo ayenera kugwira ntchitoyo chifukwa kutenthako kumachokera kutentha kwambiri kupita kutentha kochepa. Izi ndi zomwe Clausius ananena:

N'zosatheka kuti makina oziziritsira asamutse kutentha kuchokera pamalo otentha pang'ono kupita kumalo otentha kwambiri, popanda kugwira ntchito (Lamulo lachiwiri la thermodynamics—Clausius statement).

Makinawa amagwira ntchito (W) kusamutsa kutentha, kuchokera kutentha kochepa (Q)_Lkutentha kwakukulu (Q)_HKutengera kusungidwa kwa mphamvu, Q_L + W = Q_H.

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Kuti mudziwe momwe mungawonjezere mphamvu ya kutentha injini, wasayansi wa ku France dzina lake Sadi Carnot (1796-1832) anafufuza makina abwino kwambiri owerengera kalori mu 1824. Panthawiyo, lamulo loyamba la thermodynamics silinapangidwe, kapena lamulo lachiwiri la thermodynamics. Lamulo loyamba silinapangidwe chifukwa asayansi sakudziwabe kuti kutentha ndi mphamvu. Joule ndi anzake atayesa m'zaka za m'ma 1830, asayansi adapeza kuti kutentha ndi mphamvu yomwe imayenda chifukwa cha kusiyana kwa kutentha. Chifukwa chake, lamulo loyamba la thermodynamics linapangidwa pambuyo pa 1830. Sadi Carnot anali kufufuza injini yabwino kwambiri yowerengera kalori mu 1824. Kafukufuku wake kwenikweni anali woti awonjezere mphamvu ya injini ya nthunzi. Mainjini ambiri a nthunzi panthawiyo sanali ogwira ntchito bwino.

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