Kev txhais ntawm daim iav Concave
Ib hom iav uas siv hauv lub neej txhua hnub yog daim iav concave. Daim iav concave yog daim iav nkhaus, qhov twg qhov chaw cuam tshuam nkhaus rov qab. Yuav kom pab koj nkag siab, tshuaj xyuas daim duab ntawm daim iav concave ntawm sab.
Siv
Yog tias koj xav saib koj daim tawv nqaij ntawm lub ntsej muag kom meej dua thiab meej dua, tuav koj lub ntsej muag ze rau ntawm qhov chaw uas daim iav concave ci ntsa iab kom txog thaum koj daim iav ci ntsa iab loj dua thiab koj cov qhov hws pom tseeb. Koj daim iav ci ntsa iab loj dua koj lub ntsej muag vim daim iav ua rau nws loj dua, uas tshwm sim thaum koj lub ntsej muag tsawg dua qhov ntev ntawm daim iav. Thov kawm txog cov ntsiab lus ntawm daim iav concave ci ntsa iab kom nkag siab zoo dua qhov no. Vim tias lawv ua rau daim iav ci ntsa iab loj dua, cov poj niam feem ntau siv daim iav rau kev tu cev thiab cov txiv neej rau kev txiav plaub hau.
Cov iav concave kuj siv rau hauv cov teeb ci thiab lub teeb taub hau tsheb. Lub hom phiaj ntawm cov iav hauv cov teeb ci, lub teeb taub hau tsheb, lossis lwm yam teeb pom kev zoo yog kom sib luag lub teeb kom tag nrho lub teeb mus ncaj nraim pem hauv ntej. Yog tias koj qhib lub iav pem hauv ntej ntawm lub teeb ci thiab tshem daim iav, lub teeb tshwm sim yuav nthuav tawm mus rau txhua qhov kev taw qhia thiab tsis tuaj yeem ci cov khoom lossis qhov chaw ntawm txoj kev deb. Lub hauv paus ntsiab lus ua haujlwm ntawm cov iav hauv cov teeb ci lossis lub teeb taub hau tsheb tau piav qhia tom qab hauv kev sib tham txog qhov chaw tseem ceeb ntawm cov iav. Dhau li ntawm kev siv rau hauv cov teeb ci lossis lwm yam teeb pom kev zoo, cov iav kuj tseem siv rau hauv cov chaw tsim hluav taws xob hnub ci. Hauv cov chaw tsim hluav taws xob hnub ci, cov iav sau lub hnub ci thiab coj tag nrho lub teeb mus rau qhov chaw tseem ceeb ntawm daim iav, qhov twg lub nkoj tso. Lub hnub ci siv los ua kom cov dej hauv lub nkoj, qhov twg cov pa siv los tsav lub turbine los tsim hluav taws xob.
Qhov Chaw Tseem Ceeb
Yog tias qhov chaw ntawm daim iav uas cuam tshuam lub teeb ntsib ib yam khoom nyob deb heev, piv txwv li lub hnub, ces lub teeb uas lub hnub tso tawm yuav sib luag rau yam khoom. lub axis tseem ceeb daim iav, raws li pom hauv daim duab hauv qab no. Lub axis tseem ceeb yog ib txoj kab xav uas tig mus rau nruab nrab ntawm qhov chaw ntawm daim iav. Hauv daim duab hauv qab no, txoj kab axis tseem ceeb sib tshooj nrog qhov chaw sib tshuam ntawm txhua lub teeb ci ntsa iab.
Thaum ntaus rau ntawm daim iav, txhua lub teeb lossis lub teeb ntawm lub teeb ua raws li txoj cai ntawm kev cuam tshuam ntawm lub teeb. Nruab nrab ntawm txoj kab teeb ci thiab txoj kab uas cuam tshuam muaj ib txoj kab ib txwm uas yog perpendicular rau ntawm daim iav uas txoj kab teeb ci hla dhau, tab sis txoj kab ib txwm tsis tau kos. Lub kaum sab xis ntawm txoj kab teeb ci thiab txoj kab ib txwm yog tib yam li lub kaum sab xis ntawm txoj kab teeb ci cuam tshuam thiab txoj kab ib txwm. Sib piv rau daim iav tiaj tiaj uas muaj qhov chaw tiaj tiaj kom txhua txoj kab ib txwm nyob rau tib qho kev coj, hauv daim iav concave cov kab ib txwm tsis nyob rau tib qho kev coj vim tias qhov chaw ntawm daim iav yog nkhaus thiab tsis tiaj tus. Tag nrho cov kab teeb ci cuam tshuam sib tshuam ntawm ib qho chaw uas sib phim nrog lub axis tseem ceeb uas hu ua qhov chaw tseem ceeb (F). Hauv lwm lo lus, qhov chaw tsom mus rau qhov chaw yog qhov chaw duab ntawm ib yam khoom uas nyob deb heev ntawm qhov chaw iav, piv txwv li lub hnub thiab cov hnub qub.
Raws li txoj cai ntawm kev cuam tshuam ntawm lub teeb, qhov kev taw qhia ntawm lub teeb ci lossis lub teeb ci tuaj yeem thim rov qab, tsis zoo li daim duab dhau los. Yog tias lub teeb pom kev zoo xav tias nyob ntawm qhov chaw tseem ceeb ntawm daim iav, ces lub teeb ci uas tawm los ntawm cov khoom ntaus rau ntawm daim iav thiab raug cuam tshuam los ntawm daim iav. Qhov kev taw qhia ntawm lub teeb ci uas cuam tshuam yog sib luag rau lub axis tseem ceeb ntawm daim iav concave. Qhov no yog lub hauv paus ntsiab lus tom qab kev siv daim iav hauv teeb pom kev zoo, lub teeb taub hau tsheb lossis lwm yam teeb pom kev zoo, kev siv daim iav hauv cov chaw tsim hluav taws xob hnub ci
Raws li cov lus piav qhia saum toj no, nws tuaj yeem xaus lus tias yog tias muaj lub teeb pom kev nyob ntawm qhov chaw tseem ceeb ntawm daim iav, lub teeb ci uas tawm los ntawm cov khoom raug cuam tshuam los ntawm daim iav qhov twg lub teeb ci ntsa iab yog sib luag rau lub ntsiab axis ntawm daim iav. Ntawm qhov tod tes, yog tias cov khoom nyob ntawm qhov deb heev, daim duab ntawm cov khoom yog nyob ntawm qhov chaw tseem ceeb ntawm daim iav concave. Yog tias ib yam khoom ntawm qhov deb heev muaj daim duab ntawm qhov chaw tseem ceeb, daim duab ntawm cov khoom nyob qhov twg yog tias qhov deb ntawm cov khoom los ntawm qhov chaw ntawm daim iav yog finite lossis ze? Txhawm rau nkag siab qhov no, thov kawm txog lub ntsiab lus ntawm daim duab ntawm daim iav concave thiab kom nkag siab sai dua txog lub ntsiab lus, ua ntej kawm txog cov teeb tshwj xeeb ntawm daim iav concave thiab cov mis ntawm daim iav concave.
Qhov Ntev Focal
Qhov ntev focal (f) yog qhov deb ntawm qhov focal point (F) thiab qhov chaw ntawm daim iav concave. Cov hauv qab no piav qhia txog yuav ua li cas txiav txim siab qhov ntev focal ntawm daim iav concave siv lub teeb ci ntsa iab thiab lub teeb ci ntsa iab.
Qhov C yog qhov chaw nruab nrab ntawm qhov nkhaus ntawm daim iav concave. Qhov ntev focal ntawm daim iav concave yog f (focal length = f = FQ) thiab lub vojvoog ntawm qhov nkhaus ntawm daim iav concave yog r (radius of curvature = r = CQ = CP).
Lub teeb ci ntsa iab ntaus lub iav concave ntawm P thiab raug cuam tshuam rau qhov chaw tsom F. Lub kab dotted CP yog kab ib txwm. Lub teeb ci ntsa iab thiab lub teeb ci ntsa iab ua raws li txoj cai ntawm kev cuam tshuam ntawm lub teeb qhov twg lub kaum sab xis (θ) sib npaug rau lub kaum sab xis ntawm kev cuam tshuam (θ) thiab lub kaum sab xis no sib npaug rau lub kaum sab xis ntawm daim duab peb ceg PCQ (θ). Lub kaum sab xis ntawm daim duab peb ceg PCQ sib npaug rau lub kaum sab xis ntawm daim duab peb ceg CPF yog li daim duab peb ceg PFC yog daim duab peb ceg sib npaug. Vim tias daim duab peb ceg PFC yog daim duab peb ceg sib npaug ces qhov ntev ntawm PF sib npaug rau qhov ntev ntawm CF. Los ntawm kev xav tias qhov dav ntawm daim iav me dua lub vojvoog ntawm qhov nkhaus ntawm daim iav yog li qhov ntev ntawm PF raug suav tias sib npaug rau qhov ntev ntawm FQ. Vim tias CF = PF thiab PF = FQ ces CQ = 2 CF = 2 FQ. CQ = r = lub vojvoog ntawm qhov nkhaus ntawm daim iav concave thiab FQ = f = qhov ntev ntawm daim iav concave. Yog li ntawd, nws tuaj yeem xaus lus tias lub vojvoog ntawm qhov nkhaus ntawm daim iav concave (r) = 2 x qhov ntev ntawm lub iav concave (f) ntawm daim iav concave. Kev suav lej:
r = 2 f los yog f = r / 2
Duab ntxoov ntxoo
Daim iav tiaj tiaj tsuas yog tsim tau ib daim duab virtual xwb, thaum daim iav concave tuaj yeem tsim tau ob qho tib si cov duab tiag tiag thiab virtual. Seb daim duab ntawm ib yam khoom puas yog tiag lossis virtual nyob ntawm qhov deb ntawm yam khoom ntawm qhov chaw ntawm daim iav concave, thiab qhov no tau piav qhia meej hauv lub ncauj lus. daim iav concave.
Duab Ntxoo Tiag
Ib daim duab yog qhov tseeb yog tias lub teeb ci ntsa iab lossis lub teeb ci ntsa iab hla dhau qhov chaw uas daim duab nyob. Yog tias lub vijtsam raug tso rau hauv qhov chaw uas xav tau daim duab tiag tiag, lub teeb ci yuav tshwm sim ntawm lub vijtsam thiab lub teeb ci no muaj cov duab ntawm cov khoom. Qhov muaj ib daim duab tiag tiag tsim los ntawm daim iav concave yog qhov laj thawj vim li cas cov iav concave siv rau hauv cov tsom iav astronomical. Hauv cov ncauj lus ntawm cov iav kho qhov muag, koj yuav kawm tias lub peev xwm ntawm lub lens los tsim ib daim duab tiag tiag yog keeb kwm yav dhau los rau nws siv hauv cov tsom iav kho qhov muag.
Maya tus duab ntxoov ntxoo
Ib daim duab yog virtual yog tias lub teeb ci ntsa iab lossis lub teeb ci ntsa iab tsis hla dhau qhov chaw uas daim duab nyob. Yog tias lub vijtsam raug tso rau hauv qhov chaw uas xav tau daim duab virtual, yuav tsis muaj lub teeb ci ntsa iab pom ntawm lub vijtsam. Daim duab virtual/pom tseeb/cuav tsis muaj tiag, tab sis lub qhov muag tib neeg pom nws. lub teeb ci txav mus rau hauv txoj kev ncaj kom nws zoo li lub teeb txav mus ncaj ntawm qhov chaw uas tus duab ntxoov ntxoo nyob.
