Me pēhea te ki te kitea te paenga

He rārangi kati e tuwhaina e te manureva kia rua nga wahi mutunga (roto - porowhita) me mure ore (rārangi waho), ngā e kua reira e rave rahi āhuatanga motuhake, ka karanga te porowhita. Hei tauira, te equidistance hanganga ture e hiahiatia ana o ngā takoto ana i runga i tenei raina, i tetahi wāhi he te pokapū o te porowhita. Hoki te waka rererangi tautuhi e te porohita, i reira e te tahi mau āhuatanga ine. Ko ētahi o ēnei:

• pūtoro (te tawhiti i tetahi pūwāhi e takoto ana i runga taua mea, ki te pokapū, r);
• diameter (rārangi wehewehe i te porohita kia rua nga wahi e rite ana, haere i roto i rua ngā me te pokapū porohita o te porowhita, d);
• rohe numera e whakaatu ana i te rahi o te porowhita, S;
• te roa o te rārangi kati e whakaahua ana i te porowhita (i whakahuatia e te pukapuka Ḻ).

Ko te kupu, Ḻ he kore noa he āhuatanga ine o te porowhita, ko te aho kati, na te kupu whakahoki ki te pātai - me pehea ki te ako i te paenga, he hāngai ki e rua ariā āhuahanga.

Te tawhiti, rere haere te ānau kati waho āhua porohita o te ahanoa papatahi, ōrite reira te roa o te aho a taka i te reira. whakamahia tēnei aromatawai ine o te paenga e i roto i te ine o ngā tinana, engari ano hoki ka whakaaro āhua āhuahanga waitara. kua he tikanga motuhake mō te matauranga āhuahanga, me te pākoki te wā. E pā ana te reira ki te inenga ā-, i te mea he take motuhake o te mea pēnei i te paenga. I roto i Kariki, i te kupu oro «περίμετρον» ( «porohita») «περιμετρέο» ( «mehua a tawhio noa") ranei. Paenga (manureva ahua mo tetahi āhua) me te paenga (āhua porohita mo te āhua planar) ōrite te roa tapeke o te āhua rohe. take Special (te rohe o te porowhita) kua te taha ano rite te tawhiti ara ranei. Hei ako i te kaupapa "Me pēhea te ki te tātai i te roa o te porowhita", he mea e tika ana ki te haamana'o i te wae, me ratou translation.

E ai ki te ao pūnaha o SI, tetahi ara tawhiti ranei whanganga i roto i mita. Ko te kōwae taketake tenei, engari i reira e ano pärönaki. Ko reira reira e tika ana mo te hunga e whakatau ki ngā raruraru ariā, me te mahi i runga i "pehea ki te kitea te roa o te paenga o te" arahi ratou hononga:

• 1 kiromita = 1000 mita = 10000 = 100000 decimeters henimita = 1000000 mitamano;
• 1 maero = 1,609344 kiromita = 1609.344 16093.44 mita decimeters = = = 160,934.4 henimita mitamano 1.609.344;
• 1 ft = 30,48 henimita = 304,8 mitamano decimeters = 3,048 = 0,3048 = 0,0003048 mita kiromita.

He maha atu ngā wae o ine: te British (American ranei), koroheke Russian, Kariki, Japanese me etahi atu. I roto i te tikanga mo te ki a ratou mahi tātai, e tūtohu ana ki te whakamahi i te mōhiohio papamuri.

Hoki porowhita katoa āhuatanga e kotahi te mea i roto i te noa, i whakapumautia e pūtaiao o onamata. Ko nga wa katoa ōwehenga o te roa ki te diameter o te porowhita he tau tamau. Hoki te wa roa pūtaiao whakamahi tikanga rerekē (me wawetia pūmanawa motuhake, me te hangarau rorohiko), e whai ana ki te whakatū i te uara tangohia o taua tau. Kei te nuinga o te wā denoted reira e te reta Kariki «π» (korerotia rite pi). Ko te uara āwhiwhiwhi i ngā wā rerekē rerekē, engari i reira ko tetahi iti neke atu i te toru tonu. He rahikore te π tau. I teie mahana, i taea ki te whakapumautia i muri i te ira kotahi tekau trillion tohu pūtaiao. he tika hoki tātaitanga pāngarau matatini tenei tika. Otiia i roto i te whakaoti rapanga āhuahanga, te wahi e hiahiatia ana ki te whakahoki i te pātai - me pehea ki te kitea te paenga, piki te whakamahi i tenei tau ki runga ki pūāhua e rima e rua ranei: π ≈ 3,14159 ≈ 3,14.

Kei te mohiotia te reira e Ḻ / d = π = 3,14 ranei Ḻ / 2 r = π = 3,14. Na ko te mea ohie ki te whakahoki i te pātai - me pehea ki te kitea e te roa o te paenga o te pūtoro o te 1 mita ranei 2 decimeter, he diameter o 5 henimita ranei. Rato whakanuia rua te pūtoro diameter ranei o te π tau. Hoki ngā take e toru katoa i te tātai Ḻ = π • d = 3,14 • d ranei Ḻ = 2 • π • r = 2 • 3,14 • R hua whiwhi tātai e whai ake nei:

1. Ḻ = 3.14 • 2 • 1 = 6.28 m;
2. Ḻ = 3.14 • 2 • 2 DM = 12,56;
3. Ḻ = 3,14 • 5 = 15.7 cm.

Ko te mahi o kei roto i te pātai - me pehea ki te kitea e te roa o te paenga, ki te matau, tona pūtoro diameter ranei, engari te rohe o te porowhita, he iti uaua mohiotia, engari e taea hoki te whakatika i te reira. Hoki te wa roa e mohiotia ai e te wāhi porohita rite ki te hua o π me te tapawha o te pūtoro diameter o tetahi wha o te tapawha ranei: S = π • ṟ² ranei S = π • D ² / 4.

Te tātai i te pūtoro tuatahi R = √ (S / π) ranei diameter d = √ (4 • S / π), a ka te roa circumferential tātai. Ka taea e kite koe i te tauira o ngā take e rua i reira te rohe o te porowhita he rite ki te 12,56 m² me 78.5 cm²:

1. R = √ (12,56 / 3,14) = 2 m, mea Ḻ = 3.14 • 2 • 2 = 12.56 m ranei d = √ (4 • 12.56 / 3.14) = 4 m, na Ḻ = 3,14 • 4 = 12.56 m.
2. R = √ (78,5 / 3,14) = 5hm, te mea Ḻ = 3.14 • 2 • 5 = 31.4 cm ranei d = √ (4 • 78.5 / 3.14) = 10 cm na Ḻ = 3,14 • 10 = 31.4 cm.