Ngokuqinisekileyo uvile ngaphezu kwesihlandlo esinye ukuba isantya sokukhanya sesona sikhawulezayo kwindalo iphela. Inani elikhulu leethiyori kwifiziksi zisebenzisa i isantya sokukhanya. Ngumlinganiselo osekwe luluntu lwezenzululwazi oluye lwasinceda kwifiziksi kunye nenzululwazi ngeenkwenkwezi.
Kweli nqaku siza kukuxelela yonke into okufuneka uyazi malunga nesantya sokukhanya, imbali yayo, iimpawu kunye nokuba yintoni na.
Yintoni isantya sokukhanya
Isantya sokukhanya ngumlinganiselo omiselwe luluntu lwezenzululwazi kwaye lusetyenziswa ngokufanayo kwiinkalo zenzululwazi yendalo kunye nenzululwazi ngeenkwenkwezi. Isantya sokukhanya simele umgama ohanjwa kukukhanya ngexesha leyunithi.
Ukuqonda izidalwa ezisesibhakabhakeni, indlela eziziphatha ngayo, indlela imitha ye-electromagnetic esasazwa ngayo, kunye nendlela ukukhanya okubonwa ngayo ngeliso lomntu kubaluleke kakhulu ekufundeni indalo yasezulwini.
Ukuba siyawazi umgama, siyakwazi ukubona ukuba kuthatha ixesha elingakanani ukukhanya ukuhamba. Umzekelo, ukukhanya okuvela elangeni kuthatha malunga nemizuzu esi-8 kunye nemizuzwana eyi-19 ukufika eMhlabeni. Isantya sokukhanya sithathwa njengento eqhelekileyo, engaguquguqukiyo ngexesha kunye nendawo ebonakalayo. Inexabiso le-299.792.458 yeemitha ngomzuzwana, okanye i-1.080 yezigidi zeekhilomitha ngeyure.
Esi santya sinxulumene nonyaka wokukhanya, iyunithi yobude esetyenziswa ngokubanzi kwinzululwazi ngeenkwenkwezi, engumgama ohanjwa kukukhanya ngonyaka omnye. Isantya sokukhanya esikwazisayo sisantya saso kwindawo engenanto. Noko ke, ukukhanya kuhamba kwezinye izinto, njengamanzi, iglasi okanye umoya. Ukuhanjiswa kwayo kuxhomekeke kwiipropathi ezithile ze-medium, ezifana nemvume, amandla ombane kunye nezinye iimpawu ze-electromagnetic. Ke kukho imimandla ebonakalayo leyo i-electromagnetic yenza lula ukuthuthwa kwayo, kunye nezinye eziyithintelayo.
Ukuqonda ukuziphatha kokukhanya kubalulekile kungekuphela nje kwisifundo se-astronomy, kodwa nokuqonda i-physics echaphazelekayo kwizinto ezifana neesathelayithi ezijikeleza umhlaba.
Imbali ethile
AmaGrike ayengawokuqala ukubhala imvelaphi yokukhanya, awayekholelwa ukuba kwakuphuma kwizinto ngaphambi kokuba kukhutshwe umbono womntu ukuze kubanjwe. Ukukhanya kwakungacingelwa ukuba kuhamba de kwayinkulungwane ye-XNUMX, kodwa njengento nje edlulayo. Noko ke, oku kwatshintsha emva kokuba kuphawulwe ukusithwa kwelanga yinyanga. Kutshanje, uGalileo Galilei wenze iimvavanyo ezithile ezithandabuza "ukukhawuleza" komgama ohanjwa kukukhanya.
Izazinzulu ezahlukeneyo zenze iimvavanyo ezahlukeneyo, ezinye zinethamsanqa kwaye ezinye azikho, kodwa kweli xesha lesayensi lokuqala, zonke ezi zifundo zefiziksi zalandela injongo yokulinganisa isantya sokukhanya, nokuba izixhobo kunye neendlela zabo azichanekanga kwaye ezona ziphambili zazinzima. UGalileo Galilei wayengowokuqala ukwenza iimvavanyo zokulinganisa le nto, kodwa akazange afumane iziphumo eziya kunceda ukubala ixesha lokuhamba lokukhanya.
U-Ole Roemer wenza umzamo wokuqala wokulinganisa isantya sokukhanya ngo-1676 ngempumelelo. Ngokufunda iiplanethi, uRoemer wafumanisa kwisithunzi soMhlaba ebonakaliswa kumzimba weJupiter ukuba ixesha eliphakathi kokusithwa kwelanga yinyanga lifutshane njengoko umgama osuka eMhlabeni unciphile, kwaye ngokuphambanayo. Ifumene ixabiso le-214.000 yeekhilomitha ngomzuzwana, inani elamkelekileyo elinikwa inqanaba lokuchaneka ekunokulinganiswa ngalo imigama yesijikelezi-langa ngelo xesha.
Emva koko, ngo-1728, uJames Bradley naye wafunda isantya sokukhanya, kodwa ngokuqwalasela utshintsho kwiinkwenkwezi, wafumanisa ukufuduka okunxulumene nokuhamba koMhlaba ujikeleze ilanga, apho wafumana ixabiso le-301.000 yeekhilomitha ngomzuzwana.
Kuye kwasetyenziswa iindlela ezahlukahlukeneyo ukuze kuphuculwe ukuchana kwemilinganiso, ngokomzekelo, ngowe-1958 isazinzulu uFroome. wasebenzisa i-interferometer ye-microwave ukufumana ixabiso leekhilomitha ezingama-299.792,5 ngomzuzwana., eyona ichanileyo. Ukususela kwi-1970, umgangatho wemilinganiselo uphuculwe ngokomgangatho kunye nokuphuhliswa kwezixhobo ze-laser ezinomthamo omkhulu kunye nokuzinza okukhulu, kunye nokusetyenziswa kweewotshi ze-cesium ukuphucula ukuchaneka kwemilinganiselo.
Apha sibona isantya sokukhanya kwimidiya eyahlukeneyo:
- Ayinanto – 300.000 km/s
- Umoya – 2999,920 km/s
- Amanzi – 225.564 km/s
- I-Ethanol - 220.588 km / s
- Iquartz – 205.479 km/s
- Isithsaba seCrystal – 197,368 km/s
- Ikristale yeFlint: 186,335 km/s
- Idayimane - 123,967 km / s
Kuluncedo ngantoni ukwazi isantya sokukhanya?
Kwifiziksi, isantya sokukhanya sisetyenziswa njengesalathiso esisisiseko sokulinganisa nokuthelekisa izantya kwindalo iphela. sisantya esasaza ngaso imitha ye-electromagnetic, kubandakanywa ukukhanya okubonakalayo, amaza erediyo, ii-X-reyi, kunye nemitha ye-gamma. Ukukwazi ukulinganisa esi santya kusenza sikwazi ukubala imigama kunye namaxesha kwi-cosmos.
Umzekelo obalulekileyo wendlela isantya sokukhanya esisetyenziswa ngayo kwifiziksi kufundo lweenkwenkwezi. Kuba ukukhanya kwenkwenkwezi kuthatha ixesha eliqingqiweyo ukufikelela eMhlabeni, xa sijonga inkwenkwezi sijonga kwixesha elidlulileyo. Okukhona inkwenkwezi ikude, kokukhona ukukhanya kwayo kuthatha ixesha elide ukufikelela kuthi. Le propati ivumela ukuba siphande indalo yonke ngamaxesha ahlukeneyo kwimbali yayo, ekubeni sinokuhlalutya ukukhanya kweenkwenkwezi eziye zayilwa kwizigidi okanye kwanamawaka ezigidi zeminyaka eyadlulayo.
Kwi-astronomy, isantya sokukhanya sibalulekile ukubala imigama kwi-cosmos. Ukukhanya kuhamba ngesantya esingaguqukiyo esimalunga neemitha ezingama-299,792,458 ngomzuzwana kwindawo engenanto. Oku kusivumela ukuba silinganise imigama eya kwiinkwenkwezi ezikude nakwiminyele sisebenzisa ingqikelelo yeminyaka yokukhanya. Unyaka okhanyayo ngumgama ohanjwa kukukhanya ngonyaka omnye, kwaye ulingana neekhilomitha ezili-9,461 zetriliyoni. Zisebenzisa le yunithi yokulinganisa, izazi ngeenkwenkwezi zinokubona umgama oya kwizinto ezikude zeenkwenkwezi kwaye ziqonde ngcono ukwakheka kunye nobungakanani bendalo iphela.
Kwakhona, isantya sokukhanya sinxulumene nethiyori ka-Albert Einstein yonxulumano. Ngokwale thiyori, isantya sokukhanya sihlala sihleli kuzo zonke izakhelo zereferensi, enentsingiselo ebalulekileyo kwindlela esiliqonda ngayo ixesha kunye nendawo. Unxulumano olukhethekileyo noluqhelekileyo luka-Einstein lutshintshe ukuqonda kwethu ummandla wendalo kwaye kukhokelele kuphuhliso lobuchwepheshe obufana neGPS.
Ndiyathemba ukuba ngolu lwazi unokufunda ngakumbi malunga nesantya sokukhanya kunye neempawu zayo.