Indlela Yokuqonda Umqondo Wamandla Adonsela Phansi Ku-Astronomy
Amandla adonsela phansi angomunye wemibono eyisisekelo kakhulu kwezesayensi yezinkanyezi—empeleni, angabizwa ngokuthi “ulimi” oluchaza ukuthi kungani amaplanethi ejikeleza izinkanyezi, ukuthi kungani izinkanyezi zakha imithala, nokuthi kungani ukukhanya okuvela ezintweni ezikude kugoba. Nakuba kungase kuzwakale kuyinkimbinkimbi, amandla adonsela phansi angaqondwa kancane kancane: kusukela kokuhlangenwe nakho kwansuku zonke, kuqhubekele emithethweni kaNewton, bese kuqhubekela phambili ekuhlobaneni okuvamile kuka-Einstein, isisekelo sesayensi yezinkanyezi yanamuhla. Lesi sihloko sixoxa ngendlela yokuqonda amandla adonsela phansi kwesayensi yezinkanyezi ngendlela ehambisanayo nefanele.
1. Amandla adonsela phansi: kusukela kokuhlangenwe nakho kwansuku zonke kuya ezikalini ze-cosmic
Siwazi amandla adonsela phansi ngomqondo olula: izinto eziwela phansi. Kodwa kusayensi yezinkanyezi, amandla adonsela phansi akuwona nje "amandla aphansi," kodwa kunalokho adonsela phansi phakathi kwazo zonke izinto ezinesisindo (futhi, ngokuhlobana, namandla). Ngenxa yokuthi amandla adonsela phansi asebenza ngaphandle kokuthintana ngqo futhi akanawo "umkhawulo webanga" ocacile, yiwona oqhuba ukunyakaza kwezinto zasezulwini ngezinga elikhulu.
EMhlabeni, amandla adonsela phansi abonakala ebusa ngenxa yobukhulu bomhlaba kanye nokusondela kwethu kuwo. Emkhathini, amandla adonsela phansi ahlala esebenza, kodwa "umuzwa wesisindo" ungalahleka ngenxa yezimo zokuwa ngokukhululekile (isb., osomkhathi esiteshini sasemkhathini). Kubalulekile ukuqonda ukuthi amandla adonsela phansi amancane akusho ukungabikho kwamandla adonsela phansi, kodwa kunalokho ukuthi izinto zihlala zisesimweni sokuwa zizungeze uMhlaba.
2. Umthetho KaNewton Wokudonsa: isisekelo sokuqala sokuqonda imijikelezo
Indlela ejwayelekile kakhulu yokuqonda amandla adonsela phansi kwesayensi yezinkanyezi iwukusebenzisa uMthetho kaNewton we-Universal Gravitation. Lo mthetho uthi izinto ezimbili ezinobunzima ziyakhangana, futhi ubukhulu bamandla yilokhu:
– ngokulingana ngqo nomkhiqizo wobuningi babo,
– ngokulingana okuphambene nesikwele sebanga eliphakathi kwezikhungo zazo zobunzima.
Ngokwezinga, kusho ukuthi:
– Uma isisindo sento sikhulu, amandla ayo adonsela phansi aqina kakhulu.
– Uma ibanga liqhubeka, amandla adonsela phansi ayancipha ngokushesha.
Kusukela kulokhu, singaqonda ukuthi kungani iLanga libusa uhlelo lwelanga: isisindo salo sikhulu kakhulu kunesamaplanethi. Singaqonda futhi ukuthi kungani amaplanethi aseduze neLanga ehamba ngokushesha: ngoba amandla awo adonsela phansi makhulu, adinga isivinini esiphezulu sokuzungeza ukuze aqhubeke "ezungeza" iLanga ngaphandle kokuwela kulo.
3. Umjikelezo awuyona “intantayo”, kodwa uyawa njalo
Enye yezindlela eziqondakala kalula zokuqonda imijikelezo ukucabanga ngento ekhishwe isuka endaweni ephakeme kakhulu. Iwa iqonde phansi. Kodwa-ke, uma into inikezwa ijubane elikhulu ngokwanele elivundlile, izoqhubeka nokuwa, kodwa ubuso boMhlaba "buzogoba" kuyo. Umphumela: into ayikaze ishaye ubuso, bese kudalwa umjikelezo.
Kumaplanethi namasathelayithi, i-orbit iyibhalansi eguquguqukayo phakathi:
- ukuthambekela kokuhamba emgqeni oqondile (inertia),
– ukudonswa kwamandla adonsela phansi kuya enkabeni yesisindo.
Uma ijubane liphansi kakhulu, into izowela entweni ephakathi. Uma iphakeme kakhulu, into ingase iphunyuke ilandele indlela evulekile (i-parabola noma i-hyperbola), njengezinye izinkanyezi ezinomsila noma izindiza-mkhathi eziphuma ohlelweni lwelanga.
4. I-Kepler nesimo somjikelezo: imibuthano eyindilinga, hhayi ephelele
Ngaphambi kukaNewton, uJohannes Kepler wathola imithetho yokuhamba kwamaplanethi ngokusekelwe kudatha yokubuka. UKepler wabonisa ukuthi imijikelezo yamaplanethi iyizingqimba, kanti iLanga ligxile kokunye. Lokhu kwasiza ekuchazeni ukuthi kungani amabanga amaplanethi ukusuka eLangeni ehluka unyaka wonke.
Imibono emithathu kaKepler ibalulekile ekuqondeni amandla adonsela phansi:
1. Umjikelezo u-elliptical.
2. Amaplanethi ahamba ngokushesha uma eseduze neLanga futhi ahamba kancane uma ekude (umthetho wezindawo ezilinganayo).
3. Kukhona ubudlelwano phakathi kwesikhathi sokuzungeza ilanga kanye nebanga elimaphakathi neLanga.
Kamuva uNewton wachaza ukuthi imithetho kaKepler yavela ngokwemvelo ngenxa yamandla adonsela phansi. Ngakho-ke, ukuqonda iKepler kwakuyibhuloho elikhulu ukusuka ekubukeni kuya encazelweni engokwenyama.
5. Amandla adonsela phansi njengethuluzi "lokulinganisa" ubukhulu bezinto zasezulwini
Ku-astronomy, sivame ukungakwazi "ukukala" amaplanethi noma izinkanyezi ngesikali. Kodwa amandla adonsela phansi ahlinzeka ngesisombululo esihlakaniphile: isisindo singabalwa kusukela ekunyakazeni kwezinye izinto.
Ngokwesibonelo:
– Ubunzima beplanethi bungabalwa kusukela ekuzungeni kwamasathelayithi ayo.
– Ubunzima benkanyezi bungabalwa kusukela ekuzungeni kwenkanyezi ehambisana nayo (uhlelo lwenkanyezi enama-binary).
– Ubunzima bomthala bungalinganiswa ngesivinini sezinkanyezi ezizungeza isikhungo somthala.
Yingakho isayensi yezinkanyezi ithembele kakhulu kudatha ye-orbital, ukushintsha kwe-Doppler, kanye nezinkathi zokuguquka: konke kuqukethe ulwazi lwamandla adonsela phansi olwembula ubukhulu.
6. Amandla adonsela phansi ngezinga elikhulu: imithala, amaqoqo emithala, kanye nendaba emnyama
Lapho izazi zezinkanyezi zilinganisa ijubane lezinkanyezi emaphethelweni omthala, zithole ukuthi zazihamba ngokushesha kakhulu ukuba zingabala kuphela ubunzima bezinto ezibonakalayo (izinkanyezi negesi). Uma ubunzima babuncane, izinkanyezi "zazizophonswa" ngaphandle. Kodwa umthala wahlala uphelele.
Yilapho kwavela khona umqondo wezinto ezimnyama: ingxenye engabonakali engakhiphi ukukhanya kodwa enamandla adonsela phansi. Izinto ezimnyama ziyasiza ekuchazeni:
- ijika lokujikeleza kwe-galaxy,
- amandla ezinhlobo zezinkanyezi,
– ukwakheka kwezakhiwo ezinkulu zendawo yonke.
Ukuqonda amandla adonsela phansi kwezinkanyezi zanamuhla kusho nokuqonda ukuthi amandla adonsela phansi esiwabona esebenza kuwo ngokuvamile avela ezinqwabeni ezingabonakali ngqo.
7. Ubudlelwano Obujwayelekile: amandla adonsela phansi njengokugoba kwesikhala nesikhathi
Imithetho kaNewton inembe kakhulu ezimweni eziningi, kodwa kunezimo ezimbi kakhulu (isivinini esikhulu, amasimu adonsela phansi anamandla kakhulu) lapho imithetho kaNewton inganele khona. Yilapho i-Einstein's General Relativity iqala khona ukusebenza.
Ngokusho kokuhlobana okuvamile:
– amandla adonsela phansi akuwona “amandla” ngomqondo wakudala,
- isikhathi nesikhala sesikhathi se-mass kanye ne-energy curve,
– izinto nokukhanya kuhamba “ngezindlela zemvelo” (izindlela zemvelo kakhulu) ngesikhathi sesikhala esigobile.
Imiphumela ebalulekile kusayensi yezinkanyezi:
– Ukuphambuka kokukhanya ngamandla adonsela phansi (ukubona ngeso lengqondo amandla adonsela phansi): ukukhanya okuvela emithaleni ekude kungaphambukiswa yisisindo esiphakathi kwethu nomthombo wokukhanya.
– I-perihelion kaMercury: ukushintsha kwephuzu eliseduze kakhulu lomjikelezo kaMercury kufana nezibikezelo zokuhlobana okuvamile.
– Umgodi omnyama: indawo yesikhala-sesikhathi egobile kangangokuthi ngisho nokukhanya akukwazi ukuphuma ngemva kokudlula emkhathizwe wesenzakalo.
Uma uNewton esize ekuqondeni “ukuthi kungani amaplanethi ejikeleza”, ukuhlobana okuvamile kusiza ekuqondeni izenzakalo ezifana nemigodi emnyama, amagagasi adonsela phansi, kanye nesakhiwo sendawo yonke.
8. Amagagasi adonsela phansi: “ukudlidliza” kwesikhala-sesikhathi
Ukutholakala kwamagagasi adonsela phansi (okwaqinisekiswa yi-LIGO ngo-2015) kwavula indlela entsha yokufunda indawo yonke. Amagagasi adonsela phansi avela lapho izinto ezinkulu kakhulu zidlula ngokushesha okukhulu, isibonelo:
– imigodi emibili emnyama izungezana bese ekugcineni ishayisana,
– izinkanyezi ezimbili ze-neutron ziyahlangana.
Lokhu kubalulekile ngoba isayensi yezinkanyezi ayisanciki kuphela ekukhanyeni (okukhanya, umsakazo, ama-X-ray), kodwa futhi "izwa" indawo yonke ngokusebenzisa amaza esikhala-sikhathi. Ukuqonda amandla adonsela phansi manje sekuyithuluzi lokubuka, hhayi nje inkolelo-mbono.
9. Izindlela eziwusizo zokufunda amandla adonsela phansi kwesayensi yezinkanyezi
Ukuze umqondo wamandla adonsela phansi “ungene” ngempela, ezinye izinyathelo zokufunda ezisebenzayo yilezi:
1. Kusukela emqondweni wokujikeleza
Qonda ukuzungeza komhlaba njengokuwa okukhululekile okuqhubekayo. Sebenzisa izibonelo zamasathelayithi neziteshi zasemkhathini.
2. Sebenzisa ukuqhathanisa isikali
Qhathanisa amandla adonsela phansi oMhlaba, iNyanga, neLanga ukuze uthole umuzwa wemiphumela yobukhulu kanye nebanga.
3. Funda amacala angempela
Isibonelo: kungani kukhona amagagasi olwandle (ithonya leNyanga neLanga), noma kungani ama-comet enemizila ejikelezayo efana ne-elliptical.
4. Yazi imingcele kaNewton nokuthi uzoyisebenzisa nini i-Einstein's
I-Newton yayanele ukubala okuningi kwesimiso selanga, kodwa u-Einstein wayedingeka ukuze kube namasimu aqinile (imigodi emnyama) kanye nokunemba okuphezulu.
5. Landela izenzakalo zokubuka
Amalensi adonsela phansi, amajika okujikeleza kwe-galaxy, kanye namagagasi adonsela phansi “ubufakazi” bokuthi amandla adonsela phansi asebenza ezikalini ezinkulu.
Isiphetho
Ukuqonda amandla adonsela phansi kwesayensi yezinkanyezi kusho ukuqonda umshayeli oyinhloko wokunyakaza kanye nesakhiwo sendawo yonke. UNewton wanikeza ithuluzi elinamandla lokuchaza imijikelezo nokubala ubuningi bezidalwa zasezulwini. UKepler wabonisa amaphethini okujikeleza ngokusekelwe ekubonweni. U-Einstein wandisa ukuqonda kwethu ukuthi amandla adonsela phansi ukugoba kwesikhathi sesikhala okungagoba ukukhanya futhi kukhiqize amagagasi adonsela phansi. Kusukela kumaplanethi kuya kuma-galaxies, kusukela kuma-satellite kuya emigodini emnyama, amandla adonsela phansi yintambo elukwa indaba yendawo yonke.
Uma ungathanda, ngingenza inguqulo ethandwa kakhulu yalesi sihloko kubafundi besikole samabanga aphezulu, noma inguqulo yobuchwepheshe enamafomula alula nezibonelo zokubala (isb. ukubala isisindo seplanethi kusukela enkathini yokuzungeza kwesathelayithi).
