Poàⁿ-kèng

Chiàu kó͘-tián kí-hô-ha̍k ê kóng-hoat, 1 ê îⁿ (circle) iah kiû (sphere) ê 1 tiâu poàⁿ-kèng (半徑) tō sī 1 ê toan-tiám tī îⁿ-sim iah kiû-sim, 1 ê toan-tiám tī îⁿ iah kiû téng-koân ê soàⁿ-koe̍h. Ah nā îⁿ iah kiû ê poàⁿ-kèng tō sī hit tiâu soàⁿ-koe̍h ê tn̂g-tō͘. Poàⁿ-kèng sī ti̍t-kèng chi̍t-poàⁿ tn̂g.

Tī kí-hô-ha̍k, kang-têng (engineering), tô͘-lūn (graph theory), ... khah khok-chhiong ê kóng-hoat, 1 hāng mi̍h-kiāⁿ, khó-pí kóng îⁿ-thiāu (cylinder), tô͘ (graph), iah sī ki-hâi ê lêng-kiāⁿ, téng-téng... ê poàⁿ-kèng tō sī i ê tiong-sim (center) iah te̍k (axis) kaù i siōng goā-khaú ê tiám ê kī-lî (distance).

Siong-koan bûn-chiuⁿ

• ti̍t-kèng
• Oan-khiau poàⁿ-kèng (bend radius)