Ma ka ʻatikala e pili ana i hoʻouka uila a hiki nā ʻano hoʻouku uila Ua wehewehe ʻia he mau mea uila like e hoʻokuke aku kekahi i kekahi ʻoiai ʻo nā mea uila like ʻole e huki kekahi i kekahi. I nā huaʻōlelo ʻē aʻe, huki nā mea i hoʻopiʻi maikaʻi i nā mea i hoʻopiʻi maikaʻi ʻole, hoʻokuke nā mea i hoʻopiʻi maikaʻi ʻole i nā mea i hoʻopiʻi maikaʻi ʻole, a hoʻokuke nā mea i hoʻopiʻi maikaʻi ʻole i nā mea i hoʻopiʻi maikaʻi ʻole. Hōʻike kēia hanana i ke ola ʻana o kahi ikaika uila e hana ana ma luna o nā mea i hoʻopiʻi maikaʻi ʻole a me nā mea i hoʻopiʻi maikaʻi ʻole. He aha nā mea e hoʻohuli ai i ka nui o ka ikaika uila ma waena o nā mea i hoʻopiʻi ʻia me ka uila?
Ua hana ke kanaka ʻepekema Farani ʻo Charles Coulomb (1736–1806) i kekahi mau hoʻokolohua i nā makahiki 1780 e noiʻi i nā mea e hoʻohuli ai i ka nui o ka ikaika uila ma waena o nā mea i hoʻopiʻi ʻia e ka uila. Ua like ka mea hana i hoʻohana ʻia e Coulomb me ka mea a Cavendish i hoʻohana ai e noiʻi i ke kūpaʻa umekaumaha, i kapa ʻia he kaulike torsion. Ua noiʻi ʻo Coulomb i ka ikaika uila, no laila ua hoʻohana ʻo ia i ʻelua mau pōpō metala i hoʻopiʻi ʻia e ka uila, ʻoiai ua noiʻi ʻo Cavendish i ka ikaika umekaumaha, no laila ua hoʻohana ʻo ia i ʻelua mau pōpō nuipa ʻaʻole i hoʻopiʻi ʻia e ka uila.
Pehea e hana ai ka unahi torque
Pehea e pili ai ka hana ʻana o kahi unahi torque i ke kumuhana torque a i ʻole ka manawa o ka ikaika ma ka mokuna nā dinamika hoʻohuli.
ʻO ka hakahaka i loko o ke kaulike torsion he vacuum e pale aku i ka hoʻoili ʻana o ka uila ma luna o ka pōpō paʻa i ka lewa. Hana ʻia ka hoʻoholo ʻana i ka nui o ka uila ma luna o ka pōpō paʻa me ka hoʻohana ʻana i kēia ʻano hana. I ka wā mua, hana ʻia ka pōpō paʻa A i hoʻopiʻi ʻia me ka uila ma o ka conduction a i ʻole ka friction. Hoʻopili ʻia ka pōpō paʻa A i hoʻopiʻi ʻia me ka uila i ka pōpō paʻa B e kūlike mau ana me ka hoʻohana ʻana i kahi alakaʻi uila a hiki i ka wā e puʻunaue like ʻia ai ka uila o ka pōpō paʻa A me ka pōpō paʻa B. Inā he ½ ka nui o ka uila o ka pōpō paʻa A a laila he ½ ka nui o ka uila o ka pōpō paʻa B. A laila, hoʻopili ʻia ka pōpō paʻa B a me ka pōpō paʻa C me kahi alakaʻi uila a hiki i ka wā e puʻunaue like ʻia ai ka uila o ka pōpō paʻa B me ka pōpō paʻa C. Inā he ¼ ka nui o ka uila o ka pōpō paʻa B a laila he ¼ ka nui o ka uila o ka pōpō paʻa C. Loaʻa ka nui o ka uila a me ke ʻano o ka uila o ka pōpō paʻa 1 a me ka pōpō paʻa 2 ma kēia ʻano.
Hoʻopiha ʻia ka poepoe paʻa 1 a me ka poepoe paʻa 2 me ka uila i hiki ai i nā poepoe paʻa ʻelua ke kipaku kekahi i kekahi inā like ka uku uila o nā poepoe ʻelua a i ʻole e huki kekahi i kekahi inā like ʻole nā uku uila o nā poepoe ʻelua. ʻO ke ola ʻana o kahi ikaika hoʻowalewale a hoʻokuke paha ma waena o nā poepoe paʻa ʻelua i hoʻopiha ʻia me ka uila ke kumu o ka poepoe paʻa 2 e wili. Ana ʻia ke kihi o ka hele ʻana o ka poepoe paʻa 2 e hoʻoholo ai i ka ikaika uila e hana ana ma nā poepoe paʻa ʻelua.
Nā mea e hoʻohuli ai i ka ikaika uila
Ma muli o nā hoʻokolohua i hana ʻia me ka hoʻohana ʻana i ke kaulike torsion, ua ʻike ʻo Coulomb i kekahi mau mea.
– Ma kēia hoʻokolohua, ua like mau ka mamao ma waena o nā pōpō paʻa ʻelua. Ke 1 ka nui o ka uku uila ma ka pōpō paʻa 1 a ʻo 1 ka nui o ka uku uila ma ka pōpō paʻa 2 a laila 1 ka ikaika uila e hana ana ma nā pōpō paʻa ʻelua. Ke 2 ka nui o ka uku uila ma ka pōpō paʻa 1 a ʻo 2 ka nui o ka uku uila ma ka pōpō paʻa 2 a laila 4 ka ikaika uila e hana ana ma nā pōpō paʻa ʻelua. Ua hoʻoholo ʻo Coulomb ʻo ka nui o ka ikaika uila e hana ana ma nā pōpō paʻa ʻelua ua like ia me ka huahana o ka nui o ka uku ma nā pōpō paʻa ʻelua (F ≈ q1 q2).
– Ma kēia hoʻokolohua, ua like mau ka nui o ka uku ma nā pōpō paʻa ʻelua. Inā he 1 ka mamao ma waena o nā pōpō paʻa ʻelua a laila he 1 ka ikaika uila e hana ana ma nā pōpō paʻa ʻelua. Inā he 2 ka mamao ma waena o nā pōpō paʻa ʻelua a laila he ¼ ka ikaika uila e hana ana ma nā pōpō paʻa ʻelua. Ua hoʻoholo ʻo Coulomb ʻo ka nui o ka ikaika uila e hana ana ma nā pōpō paʻa ʻelua he kūlike ʻole ia me ka huinahā o ka mamao (F ≈ 1 / r2)
Ke Kānāwai o Coulomb
ʻO ke kānāwai o Coulomb he kānāwai o ka physics e wehewehe ana i ka pilina ma waena o ka ikaika uila, ka uku uila, a me ka mamao ma waena o nā uku. Ua hoʻokumu ʻia kēia kānāwai ma muli o nā hoʻokolohua a Coulomb, e like me ka mea i wehewehe ʻia ma ka ʻatikala ma mua.
Ke Kānāwai o Coulomb ʻōlelo ʻia ʻo ka nui o ka ikaika i hoʻopuka ʻia e kahi ʻāpana uila i hoʻopiʻi ʻia ma luna o kekahi ʻāpana uila i hoʻopiʻi ʻia he kūlike pololei ia me ka huahana o ka huina o nā uku o nā ʻāpana ʻelua a kūlike ʻole i ka huinahā o ka mamao ma waena o nā ʻāpana uila ʻelua. Hana kēia ikaika ma kahi laina pololei e hoʻopili ana i nā ʻāpana ʻelua. He mea hoʻokuke ka ikaika uila inā like nā uku uila o nā ʻāpana ʻelua a he mea huki ka ikaika uila inā ʻaʻole like nā uku uila o nā ʻāpana ʻelua.
Hiki ke hōʻike ʻia ke kānāwai o Coulomb ma ka hoʻohālikelike makemakika:
Ka wehewehe ʻana o ke ʻano hana:
F12 = ka ikaika uila ma waena o ka ʻāpana 1 a me ka ʻāpana 2
q1 = ka helu o nā uku ʻāpana 1
q2 = ka helu o nā uku uila o ka ʻāpana 2
r12 = ka mamao ma waena o ka ʻāpana 1 a me ka ʻāpana 2
(heluhelu ʻia: epsilon zero) = 8,854 x 10-12 C2/Nm2
k = (ke kūpaʻa o Coulomb) = 9 x 109 Nm2/C2
F21 ʻo ia ka ikaika i hoʻopuka ʻia e ka uku q2 ma ke kau ʻana q1, ʻoiai ʻo F12 ʻo ia ka ikaika i hoʻopuka ʻia e ka uku q1 ma ke kau ʻana q2. F21 a me F12 e hoʻokuke aku kekahi i kekahi ke uku ʻia ʻo q1 a me q2 like a huki kekahi i kekahi ke uku ʻia ʻo q1 a me q2 ʻaʻole like ke ʻano.
F21 a me F12 he like ka waiwai, ʻokoʻa ke kuhikuhi a hana ma nā mea like ʻole, no laila he mau hui ikaika hana-pane kēia mau ikaika ʻelua.
