dielectric

ʻO ka dielectric kahi mea hoʻokaʻawale e hoʻokaʻawale i nā papa ʻelua a i ʻole nā ​​​​pepa o ke alakaʻi ma ka capacitor. ʻO nā mea hoʻokaʻawale he mau mea hiki ʻole ke alakaʻi i ke au uila, no ka laʻana, ka plastic, ke aniani, ka pepa, a i ʻole ka lāʻau. ʻO ka hana dielectric ka hoʻonui ʻana i ka capacitance i hiki i ka capacitor ke mālama i ka uku uila hou aʻe a me ka ikehu hiki ke uila.

Hiki i kahi capacitor ke hana inā ʻaʻole e hoʻopā nā papa alakaʻi ʻelua kekahi i kekahi i ʻole e neʻe ka uku uila mai kekahi alakaʻi i kekahi. Pēlā nō, i ʻole e neʻe ka uku uila mai ke alakaʻi i ka lewa, pono ka hakahaka ma waena o nā alakaʻi ʻelua i kahi vacuum. Ma ke kumuhana e pili ana i ka papa like, ua kūkākūkā ʻia ka capacitor i ka capacitance o nā capacitors papa like i hoʻokaʻawale ʻia e kahi vacuum. Loaʻa i ka capacitance o ka capacitor i loko o kahi vacuum nā palena i hiki ai ke hoʻonui i ka capacitance, e kau i ka dielectric ma waena o nā papa ʻelua.

Hoʻonui ka dielectric i ka capacitance no ka mea e emi ana ka hiki ke uila ma waena o nā papa alakaʻi ʻelua.

No ke aha i hoʻonui ʻia ai ka capacitance o ka capacitor ma hope o ke kau ʻia ʻana o ka dielectric ma waena o nā papa ʻelua a i ʻole nā ​​​​pepa? No ka ʻike ʻana i ka pane i kēia nīnau, e hoʻomanaʻo mua i ka haʻawina e pili ana i ka hoʻouka uila. E like me nā hoʻouka uila e hoʻokuke aku kekahi i kekahi, ʻoiai ʻaʻole like nā hoʻouka uila e huki kekahi i kekahi. No ka laʻana, huki kahi hoʻouka maikaʻi i kahi hoʻouka maikaʻi ʻole akā e hoʻokuke aku i kahi hoʻouka maikaʻi. A laila no ke aha e hiki ai i nā plastics i hoʻouka maikaʻi ʻole ke huki i nā ʻāpana pepa liʻiliʻi i hoʻouka ʻole ʻia e ka uila? Hana ʻia kēia no ka mea ʻike ka ʻāpana pepa i ka polarization hoʻouka.

ʻAʻole hiki i nā electrons i loko o nā mea hoʻokaʻawale e like me ka pepa ke neʻe manuahi e like me nā electrons i loko o nā mea alakaʻi. No laila, i ka wā e lawe ʻia ai ka plastic i hoʻopiʻi maikaʻi ʻole ʻia a kokoke i ka ʻāpana pepa, ua hōʻole ʻia nā electrons i hoʻopaʻa ʻia i ka atom mai ka plastic i hoʻopiʻi maikaʻi ʻole ʻia. No laila aia ka polarization o ka hoʻopiʻi maikaʻi ʻole a me ka hoʻopiʻi maikaʻi ma ka pepa. ʻOi aku ka mamao o ka hoʻopiʻi maikaʻi ʻole ma ka pepa mai ka plastic, ʻoiai ʻo ka hoʻopiʻi maikaʻi ma ka pepa he mamao kokoke i ka plastic. A laila, huki ka hoʻopiʻi maikaʻi ʻole ma ka plastic i ka hoʻopiʻi maikaʻi ma ka ʻāpana pepa a hiki i ka neʻe ʻana o ka pepa a kokoke i ka plastic.

ʻO ke kaʻina hana polarization o ka hoʻopiʻi e hana ʻia ma nā ʻāpana pepa ua like ia me ka polarization o ka hoʻopiʻi e hana ʻia ma ka dielectric. E like me ka mea i hōʻike ʻia ma ke kiʻi ma ka ʻaoʻao hema, no ka laʻana, i ka wā mua, ʻelua wale nō ʻāpana o nā alakaʻi uila i hoʻopiʻi ʻia. Hoʻopiʻi maikaʻi ʻia ka papa hema ʻoiai ua hoʻopiʻi maikaʻi ʻole ʻia ka papa ʻākau i hiki ai ke kuhikuhi o ke kahua uila mai ka hema a i ka ʻākau.

Ma hope o ke kau ʻia ʻana o ka dielectric ma waena o nā papa alakaʻi ʻelua, huki ka uku maikaʻi ma ka papa hema i nā electrons ma ka ʻili dielectric kokoke. Eia kekahi, hoʻokuke ka uku maikaʻi ʻole ma ka papa ʻākau i nā electrons ma ka ʻili dielectric kokoke. ʻAʻole noa nā electrons i loko o ka dielectric, he insulator, e neʻe e like me nā electrons i loko o kahi alakaʻi. No laila, noho mau nā electrons i ka atom, akā aia kahi polarization o nā electrons i hoʻopiʻi maikaʻi ʻole a me nā protons i hoʻopiʻi maikaʻi ʻia, e like me ka mea i hōʻike ʻia ma ke kiʻi.

ʻO ke alo o kahi uku maikaʻi ma ka ʻaoʻao ʻākau o nā ʻātoma dielectric a me kahi uku maikaʻi ʻole ma ka ʻaoʻao hema o nā ʻātoma dielectric e hāʻawi i kahi kahua uila. ʻO ia hoʻi mai ka ʻākau a i ka hema, kahi e hoʻonāwaliwali ai i ke kahua uila i hana ʻia e ka uku uila ma ka papa alakaʻi, ʻo ia hoʻi mai ka hema a i ka ʻākau. No laila, emi ke kahua uila ʻaʻole no ka mea e emi ana ka uku uila ma nā papa ʻelua/pepa o ke alakaʻi, akā no ka mea e ʻike ʻia ke kahua uila ma ka dielectric ma ke ʻaoʻao ʻē aʻe. Inā hoʻokuʻu ʻia ka dielectric, ua hoʻi ka ikaika o ke kahua uila i hana ʻia e ka uku uila ma nā papa ʻelua a i ʻole nā ​​pepa o ke alakaʻi i ka maʻamau.

If Ua emi ka ikaika o ke kahua uila i hana ʻia e ka uku uila ma nā papa alakaʻi ʻelua, ua emi pū ka hiki ke uila ma waena o nā papa alakaʻi ʻelua. No ka mea, ua kūlike pololei ke kahua uila i ka hiki ke uila e like me ka mea i ʻōlelo ʻia ma ka hoohalike E = V / d, kahi E = kahua uila, V = hiki ke uila a me d = ka mamao ma waena o nā papa ʻelua. Inā ma mua o ka hiki ke uila i ka dielectric ʻo Vo a laila ma hope o ka dielectric, ua hoʻemi ʻia ka hiki ke uila i V e ka factor K.

Ma ke ʻano makemakika, Vo = KV a i ʻole V = Vo / K a i ʻole K = Vo / V, kahi ʻo K = dielectric constant. Vo> V i hiki ai iā K> 1.

E ʻoluʻolu e hoʻomaopopo ʻaʻole e loli ka nui o ka uku uila ma nā papa ʻelua a i ʻole nā ​​​​pepa o nā alakaʻi i like ai ka nui o ka uku hope loa me ka nui o ka uku mua (Q = Qo). Ua helu ʻia ka loli o ka capacitance o ka capacitor penei:

C = ka capacitance hope loa, Co = ka capacitance mua, Q = ka hoʻopiʻi hope loa, Qo = ka hoʻopiʻi mua, V = ka hiki hope loa, Vo = ka hiki mua, K = ka paʻa dielectric

Ma muli o ke kaulike ma luna, ua hoʻoholo ʻia he liʻiliʻi ka capacitance mua (Co) ʻoiai ʻoi aku ka nui o ka capacitance hope loa (C). Hoʻonui ʻia ka capacitance e kahi kumu o K, kahi ʻo K ka dielectric constant. ʻOkoʻa ka waiwai o ka dielectric constant o kēlā me kēia mea insulating. ʻO ka dielectric constant (K) ka hopena o ka ratio o ka capacitance o ka capacitor i ka wā e hoʻohana ai i kahi dielectric, i ka capacitance o ka capacitor i ka wā ʻaʻole e hoʻohana i kahi dielectric.

Hoʻonui ka capacitance dielectric no ka mea e emi ana ka mamao ma waena o nā papa alakaʻi ʻelua

ʻO kekahi hana dielectric ʻo ia ka hoʻemi ʻana i ka mamao (d) ma waena o nā papa alakaʻi ʻelua. I mea e hoʻonui ai ke kahua uila (E) a me ka voltage uila (V) ma waena o nā papa ʻelua a i ʻole nā ​​​​papa o nā alakaʻi, e like me ka mea i ʻōlelo ʻia e ka hoohalike E = V / d. Inā hoʻonui ke kahua uila a me ka voltage uila ma waena o nā papa ʻelua a i ʻole nā ​​​​papa, a laila hoʻonui ka capacitance o ka capacitor.

Inā kūlike nā capacitors i nīnau ʻia, ua helu ʻia ka capacitance me ka hoʻohana ʻana i kēia ʻano hana:

Ma muli o nā ʻano hana ʻelua ma luna, hiki ke hoʻoholo ʻia e hiki ke hoʻonui ʻia ka capacitance (C) o nā capacitors pā like ma ka hōʻemi ʻana i ka mamao ma waena o nā pā ʻelua a i ʻole nā ​​​​pepa alakaʻi (d).

Hoʻonui ka capacitance dielectric no ka mea e hoʻonui ana ka capacitance o ka capacitor

Hana ʻia ka dielectric me ka mea hoʻokaʻawale, inā aia ia i loko o kahi kahua uila ikaika, e hōʻino ʻia. Hana ʻia ka hōʻino dielectric i ka wā e ikaika loa ai ke kahua uila e hiki ai ke hoʻoneʻe i nā electrons mai ka ʻātoma, a laila kuʻi nā electrons i nā electrons ma nā ʻātoma ʻē aʻe i hiki ai ke kahe o nā electrons i loko o ka dielectric. I nā huaʻōlelo ʻē aʻe, ʻo ka hōʻino dielectric ke kumu o ka dielectric ʻo ia ka insulator uila e lilo i alakaʻi uila.

I mea e pale aku ai i ka pōʻino, ʻo kēlā me kēia dielectric i hana ʻia mai kahi mea insulating i loaʻa kahi waiwai kahua uila kiʻekiʻe loa e hiki ke paʻa, i kapa ʻia ʻo ka ikaika dielectric. ʻOi aku ka ikaika dielectric o ka mea insulating ma mua o ka ikaika dielectric o ka lewa a he ʻokoʻa ka ikaika dielectric o kēlā me kēia mea insulating, he liʻiliʻi kekahi a he nui kekahi. No laila, inā hoʻohana ʻia kahi dielectric me ka ikaika dielectric nui, ʻoi aku ka nui o ke kahua uila e hiki ke paʻa a ʻoi aku hoʻi ka voltage e hiki ke paʻa. Inā ʻoi aku ka nui o ke kahua uila a me ka voltage uila i hana ʻia e nā papa ʻelua a i ʻole nā ​​​​pepa o ke alakaʻi, ʻoi aku ka nui o ka nui o ka uku uila e hiki ke hoʻokipa ʻia e ka papa alakaʻi. ʻO ka nui o ka uku i loko o ka papa alakaʻi, ʻoi aku ka nui o ka capacitance o ka capacitor.