Puresha

 

[Pressure]

 

 

Puresha [P] ifosi.

Fosi isimba rinoita kuti chinhu chaka mira chifambe, nechinhu chiri kufamba chitsauke kubva kwachaka nanga. Ma‘SI’ [esi ai] yuniti efosi maNyutoni [N]. Nyutoni rimwe chete (1.0N) ifosi kana kuti simba rinoita kuti chinhu chine uremo hwekiro rimwe chete chirambe chichi pamhidza uchimbi hwacho nemita imwe chete pasekondi rega rega [N= kg m s¬2].

 

Simba regiravhiti rino kakata chinhu chine uremo hwekiro rimwechete nesimba rinoita kuti chidonhe neuchimbi [sipidhi] inoramba ichikwira ne9.81m pasekondi yega yega. Izvi zvino reva kuti giravhiti rine simba re9.81N. Saka simba re9.81N zvimwe chete nekuti kiro rimwe chete.

 

Puresha ifosi raka dzvinya [udzvinyi]panhu kana kuti rakapararira panzvimbo. Ino rehwa ichinzi fosi [udzvinyi] payuniti yeeriya. S.I. yuniti yepuresha iPasika [Pa]. Yuniti imwe chete yepuresha [1.0Pa] ifosi renyutoni imwe chete paeriya yemita imwechete [1.0m2].

 

Sezvo simba rekukakata regiravhiti manyutoni 9.81N pakiro rega rega, nyutoni imwe chete yakaenzana nemagiramu 102g : 1.0N = 102gm. Kapuresha kepasika imwe chete, kanoti kari 1.0N pasikweya mita imwechete kana kuti magiramu 102.0gm pasikweya mita, kadikidiki zvekuti tino wanzo sevenzesa makiropasika [kPa].

 

Simba regiravhiti rino kakatawo mweya wakati komberedza richiita kuti uve nehuremo [udzvinyi]. Kukakata uku kunoita kuti mweya uwande pasi patiri uchiita mushoma kumanhengatenga kuno famba ndege nekumwewo kure kure kunopfuura ipapa. Simba rehuremo hunoita mweya tiri panyanza / pagungwa kunonzi puresha yeatimosifiye. Puresha iyi makiropasika zana: [100.0kPa], kana kuti bhar rimwe [1.0bar].

 

Muerero [F] mupimo wehuwandu wezvinoerera [Q], zvakaita semvura kana mweya, munguva inenge yagurwa  [muguri wenguva: t].

F = Q/t

Kana mvura ichierera isina ubvundu inenge ichi nyatso tsvedzerera. Yepakati inenge ichierera zvine chichimbi chino pfuura iyo iri kumadziro kana kuti mahombekombe. Yemudzirodziro inenge isingatomboerera, yepakati ichierera zvine chichimbi chino peta kana kairi kese maerero emvura yose. Mvura kana mweya inoerera kana kutevedza nemumapombi ndiwo muerero wayo.

 

Kuti mvura kana mweya ierere panotoda kuti pave nechasunda kana kudhonza. Saka kuri kubva zvaerera kunototi kuve nepuresha yakapinda kuri kuendwa.

 

Fµ P : Q/t µ P

Kuerera kune tadziso [rizisitenzi: R]. Panoti  tadziso yehumanikani hwepombi nehurefu hwayo, kugoti hukobvu hwechinoerera [vhisikositi], kugoti wo chinama [hunama] kumudziyo [firikishoni] .

 

Q/t = RP    

Zvino R = pd4

                           hl

d = upamhi hwepombi

h= ukobvu hwechinoerera

l  = urefu hwepombi

 

Saka : Q/t =   pd4    P

                       hl

 

Chierera chinogona kunge chaka bvunduka [tebulenti] pamaerero acho. Kuerera kune mutsvedzerero kuno tsiviwa nekuerera kune mazura.

 

Mayuniti ‘Systeme Internationale [SI]’

ekupima nawo [mayuniti emupimo]

 

Chikamu chino shandiswa kupimisa hurefu hwechinhu

 [bimo rehurefu: unit of length] imita.[m]

bimo renguva: unit of time isekondi [s]

bimo rehuzere: unit of volume: imita rutatu [m3], mita kiubhu

bimo  rehuremo: unit of mass: ikirogiramu [Kg]

bimo rehudziya: unit of temperature: ikeruvini [K]

bimo rehujeko: unit of luminosity: ikandera [cd]

bimo rehuwandu hwechinhu: unit of amount of substance: imoli [mol]

bimo rehuwandu hwemagetsi: unit of electrical current: iampa [A]

 

Kuti bimo zvino fanana nekuti ‘unit of measure’ paChiRungu, sezvakaita mita. [Nhai, kuti tizive hutarangano hwakaita nyeradzi mudenga,]Mapimo kureva zvimwechetezvo muhuwandu. Asi mupimo zvoreva ‘a measurement’ fanika kuti ‘madziro aita mupimo  mamita 5.01’. Kana toda kuzvireva muhuwandu toti mipimo [‘midziro yaita mipimo inoti mamita 5.01, 5.73, 5.98 etc’ ]. Zvino chipimiso chinhu chekupimisa, zvakaita serura, kana sikero kana jagi rine man’an’a ekurakidza huzere. Mapimiro maitirwo acho ekupima.

 

Asi ‘gamu rehurefu’ kana kuti ‘muguri wenguva / urefu / uzere etc’ zvino reva ‘unit length’ mita, kiromita, maira, raitiyee nedzimwewo nzira dzekudoma hurefu. ‘Unit length’ ne ‘unit of length’ zvakasiyana. Muenzaniso kuti : speed is distance travelled in unit time. Apa mayuniti ehurefu neenguva haana basa kuti mamita here kana kuti araitiyee, chero azivikanwa. Ndizvo zvimwe nenguva yacho, ingava masekondi kana mwedzi chaiyo. Saka ‘uchimbi rwendo rwafambwa mugamu renguva’.

 

Duramazwi Guru reChiShona rinotsanangudza mazwi aya:

chipimiso: chinhu chino shandiswa kueyera

chipimo: 1.iyuniti yeku pima 2. mudziyo wekuyeresa

chiyereso: chinhu chese chino shandiswa kupima

chiyero: chiyereso

chiyerwa: chipimo chimwe chete

chierwa: ‘kuona kwangu ndokwo kuti apa pachabuda zvierwa zvakawanda’.

yero: zvierwa zvakawanda

chienzaniso: chiyero

eresedza: kupima chinhu chobva chakwanirana nezvinodiwa

eresera: kugona kupima chinhu

kuererana: kuenzana

 

 

 

Farai Madzimbamuto

 

One Response to “Puresha”

  1. Mabwe Says:

    http://sn.wikipedia.org/wiki/Tsamaniso

    Onayi chinyorwa ichi

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