I roto i tenei whakaputanga, ka whakaaro tatou me pehea te kimi i te radius o te awheawhe e taiawhio ana i te porotaka matau, tae atu ki tona horahanga mata me te rōrahi o te poi e herea ana e tenei awheawhe.
Te kimi i te radius o te poroporo/poro
Ka taea te korero mo tetahi (me etahi atu kupu, whakauruhia he porotakaro ki roto i te poi) - engari kotahi anake.
- Ko te pokapū o taua awheawhe ko te pokapū o te rango, i roto i to maatau he tohu O.
- O1 и O2 ko nga pokapu o nga turanga o te rango.
- O1O2 – teitei porotakaroa (H).
- OO1 = OO2 = h/2.
Ka kitea ko te radius o te porowhita porohita (KO KOE), te haurua o te teitei o te rango (OO1) me te radius o tona turanga (O1E) hanga he tapatoru tika OO1E.
Ma te whakamahi i tenei ka kitea te whakapae o tenei tapatoru, koinei hoki te pūtoro o te porowhita kua whakawhāitihia e pā ana ki te rango kua hoatu:
Ma te mohio ki te radius o te porowhita, ka taea e koe te tatau i te horahanga (S) tona mata me tona rōrahi (V) awheawhe herea e te awheawhe:
- S = 4 ⋅ π ⋅ R2
- S = 4/3 ⋅ π ⋅ R3
Tuhipoka: π he rite te 3,14 te porotaka.