ʻO ke kūlana mua no ke kaulike o ke kino paʻa :
ʻŌlelo ke Kānāwai ʻElua o Newton inā ʻaʻole like ka ikaika hopena e hana ana ma luna o kahi mea (ua manaʻo ʻia ka mea he ʻāpana) me ka ʻole, a laila e neʻe ka mea me ka wikiwiki mau kahi e like ai ke kuhikuhi o ka neʻe ʻana o ka mea me ke kuhikuhi o ka ikaika hopena. Inā ʻole ka ikaika hopena, a laila ua hoʻomaha ka mea a i ʻole ke neʻe nei ka mea ma ka wikiwiki mau.
Ke kū mālie a neʻe paha kahi mea ma ka wikiwiki mau, ʻaʻohe wikiwiki o ka mea (a). No ka mea, ʻo ka wikiwiki (a) = 0, loli ke kaulike ma luna nei i:
Hiki ke hoʻokaʻawale ʻia kēia kaulike i kona mau ʻāpana ma ke axis-x, axis-y a me ke axis-z.
Inā hana nā ikaika ma ke kuhikuhi ʻaoʻao wale nō, a laila hoʻohana ʻia ka hoohalike 1. Inā hana nā ikaika ma ke kuhikuhi kū pololei wale nō, a laila hoʻohana ʻia ka hoohalike 2. Inā hana nā ikaika ma kahi mokulele (ʻelua ana), a laila hoʻohana ʻia nā hoohalike 1 a me 2. Inā hana nā ikaika ma kahi ākea (ʻekolu ana), a laila hoʻohana ʻia nā hoohalike 1, 2 a me 3.
He nui vector ka ikaika, loaʻa iā ia ka nui a me ke kuhikuhi. E pili ana i nā hoʻonohonoho Cartesian (x, y, a me z axes) a e like me nā lula, inā kūlike ka ikaika i ka axis x maikaʻi ʻole (ma ka hema) a i ʻole kūlike ka ikaika i ka axis y maikaʻi ʻole (i lalo), a laila maikaʻi ʻole ka ikaika. I ka ʻaoʻao ʻē aʻe, inā kūlike ka ikaika i ka axis x maikaʻi (ma ka ʻākau) a i ʻole kūlike ka ikaika i ka axis y maikaʻi (i luna), a laila maikaʻi ka ikaika.
Laʻana 1.
Kapekuʻi:
F = ka ikaika tensile, fg = ka ikaika friction, N = ka ikaika maʻamau, w = umekaumaha, m = nuipaʻa, g = wikiwiki ma muli o ke umekaumaha.
Ua hoʻomaha kahi mea no ka mea ʻo ka huina o nā ikaika a pau e hana ana ma luna o ka mea he ʻole.
E nānā hou i kēlā me kēia ikaika e hana ana ma ka mea.
Nā ikaika e hana ana ma ke kuhikuhi ʻaoʻao (axis-x):
Ka ikaika tensile (F) a me ka ikaika friction (fg) he like ka nui akā ʻokoʻa nā kuhikuhi. Aia ke kuhikuhi o ka ikaika tensile i ka ʻākau a i ʻole ma ke axis x maikaʻi (ikaika maikaʻi), ʻo ke kuhikuhi o ka ikaika friction i ka hema a i ʻole ma ke axis x maikaʻi ʻole (hōʻailona maikaʻi ʻole). No ka mea, ua like ka nui o nā ikaika ʻelua (i hōʻike ʻia e ka lōʻihi o ka pua like) a ua kūʻē ke kuhikuhi o nā ikaika ʻelua, ua like ka huina o kēia mau ikaika ʻelua me ka ʻole.
Nā ikaika e hana ana ma ke kuhikuhi kū pololei (axis-y):
Ma ka ʻāpana kū pololei (axis-y) aia kahi ikaika umekaumaha (w) a me kahi ikaika maʻamau (N). ʻO ke kuhikuhi o ka ikaika umekaumaha he kū pololei i ke kikowaena o ka Honua a i ʻole ma ke kuhikuhi o ka axis-y maikaʻi ʻole (ikaika me kahi hōʻailona maikaʻi ʻole), ʻoiai ʻo ka ikaika maʻamau ma ke kuhikuhi o ka axis-y maikaʻi (ikaika me kahi hōʻailona maikaʻi). Ua like ka nui o kēia mau ikaika ʻelua akā ua kūʻē ko lākou mau kuhikuhi, no laila ua hoʻopau nā ikaika ʻelua kekahi i kekahi.
Ua hoʻomaha ka mea ma ka laʻana ma luna no ka mea ʻo ka hopena o ka ikaika e hana ana ma ka mea, ma ka axis ākea a me ke axis kū, ua like ia me ka ʻole.
Laʻana 2.
ʻAʻole hōʻike ʻia ke koʻikoʻi a me nā mana maʻamau e hana ana ma kēia mea no ka mea ke hoʻopau nei lāua kekahi i kekahi. Inā hoʻopili ʻia kahi mana F i nā wēlau ʻelua o ka mea e like me ka mea i hōʻike ʻia ma ke kiʻi, ua like ka nui o nā mana ʻelua akā ma nā ʻaoʻao ʻē aʻe. E noho paʻa anei ka mea?
I mea e kōkua ai iā ʻoe e hoʻomaopopo i kēia, e kau i kahi puke ma luna o kahi papaʻaina. I ka wā mua, ua kū ka puke no ka mea ʻo ka hopena o ka ikaika ma ka puke he ʻole. A laila, e hoʻopili i kahi ikaika ma nā ʻaoʻao ʻelua o ka puke, e like me ka mea i hōʻike ʻia ma ke kiʻi. Inā hoʻopili ʻia kahi ikaika i ka hopena o ka puke me ka nui a me ke kuhikuhi e like me ka mea i hōʻike ʻia ma ke kiʻi, ua like kēia me ka hoʻohuli ʻana i ka puke a ʻoiaʻiʻo e hoʻohuli ka puke. Hoʻohuli ka puke no ka mea aia kahi manawa o ka ikaika i hoʻokumu ʻia e ka ikaika F. Aia ke axis o ka hoʻohuli ma waenakonu o ka puke. Inā ʻaʻohe ikaika frictional e hana ana ma ka mea, ʻo ka hopena o ka manawa o ka ikaika ka huina o nā manawa o ka ikaika i hana ʻia e nā mana ʻelua F. ʻO ke kuhikuhi o ka hoʻohuli ʻana o ka mea he uaki ia i mea e maikaʻi ʻole ai nā manawa ʻelua o ka ikaika.
ʻO ke kūlana ʻelua no ke kaulike o ke kino paʻa
Ma muli o ka laʻana 2 ma luna, hiki ke hoʻoholo ʻia inā ʻaʻole ʻo ka hopena o ka manawa o ka ikaika ma luna o kahi mea he zero (ua manaʻo ʻia ka mea he mea paʻa), a laila e wili ka mea.
I mea e ʻole ai ke wili ʻana o kahi mea (ʻaʻole e neʻe), pono ka hopena o ka ikaika he ʻole. Ke wili ʻole kahi mea, ʻaʻohe ona wikiwiki angular. No ka mea he ʻole ka wikiwiki angular, loli ke kaulike ma luna nei i:
Nā haumāna laʻana o nā nīnau kaulike ʻāpana a hiki laʻana o nā nīnau kaulike kino paʻa.
