Ubuningi obuyisisekelo nobuvelayo yibo ubuningi obubonakalayo obusivumela ukuthi siveze noma yiluphi ubuningi noma ukulinganiswa kwemizimba. Ukuhlola kuyisici esiyisisekelo sefiziksi nezinye isayensi yemvelo. Imibono kanye neminye imibono iqinisekiswa futhi iqiniswa njengeqiniso lesayensi ngokusebenzisa ukuhlolwa.
Isithombe esingenhla sibonisa amayunithi okukalwa ngawo amanani ayisisekelo namawakhi. Isisindo sikalwa ngamakhilogremu, ibanga ngamamitha, isikhathi ngemizuzwana, ama-ampere... Isigaba esilandelayo sizochaza lezi ngokuningiliziwe.
Izilinganiso ziyingxenye ebalulekile yokuhlolwa, lapho ubukhulu nobudlelwano phakathi kwamanani ahlukahlukene omzimba kusetshenziswa ukuze kuqinisekiswe iqiniso lethiyori noma i-hypothesis.
Izinhlobo zobukhulu: eziyisisekelo futhi ezitholakalayo
Izinkomba eziyinhloko
Kusistimu ngayinye yamayunithi, isethi yamayunithi ayisisekelo ichazwa ukuthi amanani awo aphathekayo abizwa ngamanani ayisisekelo.
Amayunithi ayisisekelo achazwa ngokuzimela, futhi amanani ngokuvamile alinganiseka ngokuqondile ohlelweni lomzimba.
Ngokuvamile, isistimu yamayunithi idinga amayunithi amathathu emishini (isisindo, ubude, nesikhathi). Iyunithi kagesi nayo iyadingeka.
Amanani angancikile kunoma yiliphi elinye inani elibonakalayo lokulinganisa aziwa njengamanani ayisisekelo, awancikile kunoma yiliphi elinye inani elingavezwa. Kukhona isamba sobukhulu obuyisisekelo obuyisikhombisa:
1- Isisindo: kilogram (kg)
Ichazwa ngenqwaba yesilinda esiyisibonelo se-platinum-iridium egcinwe ku-International Bureau of Weights and Measures e-Paris, e-France.
Amakhophi alo silinda agcinwa amazwe amaningi awasebenzisayo ukuze alinganise futhi aqhathanise izisindo.
2- Ubude: imitha (m)
Kuchazwa njengobude bendlela ehanjwe ukukhanya esikhathini esiyimizuzwana eyi-1/299792458 ncamashi.
3- Isikhathi: isekhondi (s)
Ngokusho kwe-International System of Units, yisikhathi sezikhathi eziyi-192.631.770 zokuzungeza ukukhanya okukhishwa i-athomu ye-cesium-133, ehambisana noshintsho phakathi kwamazinga amabili we-hyperfine wezwe eliphansi. Lokhu kunqunywa kusetshenziswa amawashi e-athomu anembe kakhulu.
4- Ugesi wamanje: i-ampere (A)
Linganisa ukushuba kwamandla kagesi. Ichazwa njengeyamanje engaguquki ukuthi, uma igeleza ngamakhondaktha amabili aqondile ahambisanayo anobude obungenamkhawulo kanye nesigaba esiphambanayo esiyindilinga esinganakwa, lapho iqhelelene ngemitha elingu-1 endaweni engenalutho, izokhiqiza amandla alingana no-2 × 10-7 Newtons imitha ngayinye yobude phakathi kwalawa makhondatha.
Nakuba kungase kubonakale sengathi ishaja kagesi bekufanele isetshenziswe njengeyunithi yesisekelo, ukulinganisa kwamanje kulula kakhulu ngakho-ke kukhethwe njengeyunithi yesisekelo evamile.
5- Izinga lokushisa: Kelvin (K)
Ngokusho kwe-International System of Units, i-kelvin iyi-1/273,16 ncamashi izinga lokushisa le-thermodynamic lephoyinti elithathu lamanzi.
Iphoyinti lamanzi eliphindwe kathathu izinga lokushisa eligxilile nokucindezela lapho izimo eziqinile, eziwuketshezi, kanye negesi zingaba khona ngesikhathi esisodwa.
6- Ukuqina okukhanyayo: ikhandlela (cd)
Ikala ukushuba kokukhanya komthombo okhipha imisebe yefrikhwensi engashintshi engu-540 × 1012 Hz, ngokushuba okukhazimulayo okungu-1/683 watts ngesitiriyo ngasinye kunoma iyiphi indlela.
7- imvukuzane (mol)
Imvukuzane inani lezinto eziqukethe izinto eziningi njengoba kunama-athomu ku-0,012 kg we-carbon-12.
Isibonelo: ubukhulu bobukhulu obuyisisekelo bungalinganiswa ngokuqondile kusetshenziswa ibhalansi ngakho-ke akuncikile kobunye ubukhulu.
Amanani atholiwe
Amanani atholakele akhiwa umkhiqizo wamandla amayunithi ayisisekelo. Ngamanye amazwi, lawa magugu atholakala ekusetshenzisweni kwamayunithi ayisisekelo.
Lawa mayunithi awachazwanga ngokuzimela, njengoba ancike encazelweni yamanye amayunithi. Amanani ahlotshaniswa namayunithi atholiwe abizwa ngamanani atholakele.
Isibonelo, cabangela isivinini se-vector quantity. Ngokukala ibanga elihanjwe yinto kanye nesikhathi esithathiweyo, isilinganiso sesivinini sento singanqunywa. Ngakho-ke, isivinini siwubukhulu obususelwe.
Ishaji kagesi nayo iyinani elitholiwe elinikezwa umkhiqizo wokugeleza kwamanje kanye nesikhathi esidlulile.
Ngaphandle kwamanani angu-7 ayisisekelo ashiwo ngenhla, wonke amanye amanani athathwa. Ezinye izibonelo zamanani atholiwe yilezi:
1- Iyunithi yomsebenzi: joule noma ujulienne (J)
Kungumsebenzi owenziwa lapho iphuzu lokusetshenziswa kwamandla e-newton eyodwa (1 N) lihambisa ibanga lemitha elilodwa (1 m) lapho liqonda khona amandla.
2- Amandla: Newton (N)
Yila mandla, lapho esetshenziswa emzimbeni onesisindo sekhilogremu elilodwa (1 kg), akhiqiza ukusheshisa kwemitha elilodwa ngomzuzwana (1 mxs 2 ).
3- Ingcindezi: ama-pascal (Pa)
Ukucindezela okuvela lapho amandla e-newton eyodwa (1 N) esetshenziswa ngokulinganayo nangokuqondile endaweni engamamitha-skwele eyodwa (1 m² ).
4- Amandla: watt noma watt (W)
Amandla akhiqiza ukukhiqizwa kwamandla ngesilinganiso sejoule eyodwa ngomzuzwana (1 J xs).
5- Ukushaja kagesi: i-coulomb noma i-coulomb (C)
Inani leshaje kagesi ethuthwa ngomzuzwana owodwa (isekhondi elingu-1) ngomsinga we-amp eyodwa (1 A).
6- Amandla kagesi: i-volt (V)
Umehluko ongaba khona phakathi kwamaphoyinti amabili ekhebula elibambayo elithwala igagasi elingaguquki le-amplifier eyodwa (1 A), lapho amandla ahlakazekayo phakathi kwalawa maphoyinti eyi-watt eyodwa (1 W).
7- Ukumelana nogesi: ohm noma ohm (Ω)
Linganisa ukumelana nogesi. Ikakhulukazi, lokho okukhona phakathi kwamaphoyinti amabili ekhondatha lapho umehluko ongaguquki ongaba khona wevolthi eyodwa (1 V), usetshenziswa phakathi kwalawo maphuzu amabili, ukhiqiza i-current ye-amp eyodwa (1 A), lapho ikhondatha ingumthombo wanoma yimaphi amandla e-electromotive.
8- Imvamisa: i-hertz noma i-hertz (Hz)
Imvamisa yento yezikhathi ezithile lapho isikhathi sayo siyisekhondi elilodwa (isekhondi elingu-1).
Izinkomba
- Izilinganiso Zesayensi Ye-Graden H.: Amanani, Amayunithi, kanye Neziqalo (2007). I-Science Curriculum Inc.
- I-Gupta A. Umehluko Phakathi Kwamanani Ayisisekelo kanye Namanani Atholakalayo (2016). Kubuyiswe ku: bscshortnote.com.
- Nicodemos G. Uyini umehluko phakathi kwenani eliyisisekelo kanye nenani elitholiwe? (2010). Ithathwe ku: ezinearticles.com.
- Okoh D, Onah H. Eze A. Ugwuanyi J, Obetta E. Izilinganiso ku-physics: fundamental and derived quantities (2016). Inkundla ye-Ambrose izimele ku-CreateSpace.
- I-Oyetoke L. Yiziphi Izibalo Eziyisisekelo/ Ezitholakalayo kanye namayunithi (2016). Ithathwe ku: academicglobe.com.
- Semat H, Katz R. Physics, Isahluko 1: Inani eliyisisekelo (1958). Robert Katz Publications.
- Sharma S, Kandpal MS. I-Discovering Physics (1997). ENew Delhi: I-Hemkunt Press.