Tiān-hō

Tiān-hō ū hun nn̄g chióng tiān-sèng: chiàⁿ-tiān-hō (Eng-gí: positive charge, hû-hō: ${\displaystyle +}$ ) kap hū-tiān-hō (Eng-gí: negative charge, hû-hō: ${\displaystyle -}$ ). Tông-sèng tiān-hō ē hō͘-siong pâi-thek, í-sèng tiān-hō ē hō͘-siong khip-ín.

Tiān-hō ê chē-chió tō sī tiān-hō-liōng ia̍h sī tiān-liōng. Tī sò͘-ha̍k-sek lāi-té, it-poaⁿ lóng sī iōng sió-siá ê Lô-má-jī ${\displaystyle q}$  lâi tāi-piáu tiān-hō ia̍h sī tiān-liōng. Chiàⁿ tiān-hō ê tiān-liōng tio̍h ài iōng chiàⁿ-sò͘ lâi sǹg (${\displaystyle q>0}$ ), hū tiān-hō--ê tio̍h ài iōng hū-sò͘ lâi sǹg (${\displaystyle q<0}$ ), Chiàⁿ, hū tiān-hō mā ē-sái sio-tú, chhun--ê tō kiò-chò chēng tiān-hō (Eng-gí: net charge). Bô chēng tiān-hō ê mi̍h-kiāⁿ tō hō-chò sī tiong-sèng--ê (Eng-gí: neutral).

Tiān-hō ê SI tan-ūi sī coulomb (hû-hō: C), chit ê miâ lâi-chū Hoat-kok bu̍t-lí-ha̍k-ka Charles-Augustin de Coulomb. Coulomb sī chi̍t chióng ián-seng tan-ūi ē-tàng iōng koh-khah ki-pún ê tan-ūi lâi piáu-ta̍t. In-ūi tiān-hō ê liōng-kong sī tiān-liû tan-ūi sêng-í sî-kan tan-ūi, phì-lūn-kóng 1 coulomb = 1 ampere × 1 bió.

Tû-liáu coulomb, tiān-hō koh ū chi̍t-kóa-á pa̍t-ê tan-ūi.

• Tī bu̍t-lí kap hòa-ha̍k, ū-sî ē iōng ki-pún tiān-hō ${\displaystyle e}$  chò tan-ūi.
• Tī tiān-hòa-ha̍k, ē iōng Faraday siông-sò͘ tāi-piáu chi̍t mole tiān-chú ê tiān-liōng.
• Tī tiān-ki kang-têng, ampere-tiám-cheng (A⋅h) ia̍h hô-ampere-tiám-cheng (mA⋅h) khah chia̍p teh iōng, chhiūⁿ chi̍t lia̍p AA-hêng ta-tiān-tî ê tiān-liōng chha-put-to ū 2 kàu 3 A⋅h.

Tiān-hō sī siú-hêng--ê (Eng-gí: conserved). Che ì-sù sī kóng, ko͘-li̍p hē-thóng ê chēng tiān-hō-liōng put-piàn.

20 sè-kí chho͘, Robert Andrews Milikan ê iû-tih si̍t-giām chèng-bêng tiān-hō sī liōng-chú-hòa--ê. Che ì-sù sī kóng, ē-ēng-tit chū-iû chûn-chāi ê tiān-hō, i ê tiān-liōng it-tēng sī siōng chió tan-ūi ê chéng-sò͘ pōe. Chit ê siōng chió tan-ūi hō͘ lâng kiò-chò ki-pún tiān-hō, hû-hō sī ${\displaystyle e}$ , i ê tat chha-put-to sī ${\displaystyle 1.602\times 10^{-19}~{\text{C}}}$ . Sui-jiân quark chit khoán lia̍p-chú bô hû-ha̍p liōng-chú-hòa, in ê tiān-liōng lóng sī ${\textstyle {\frac {1}{3}}e}$  ê pōe-sò͘, tān-sī in it-tēng ē kiat-ha̍p chò-hóe, chiâⁿ-chò tiān-liōng ûi ${\displaystyle e}$  ê chéng-sò͘ pōe ê lia̍p-chú.

Tiān-hō sī iû chhù-goân-chú lia̍p-chú só͘ chah--ê. It-poaⁿ bu̍t-chit ê chiàⁿ tiān-hō kap hū tiān-hō hun-pia̍t sī chit-chú kap tiān-chú só͘ chah--ê. Chit-chú ê tiān-liōng sī ${\displaystyle +e}$ , tiān-chú ê tiān-liōng sī ${\displaystyle -e}$ .

Tiān-hō ē thàu-kòe tiān-chû-tiûⁿ lâi kap pa̍t-ê tiān-hō ū kau-hō͘ chok-iōng, che tō sī tiān-chû-la̍t, mā sī sì chióng ki-pún-la̍t chi it. Tiān-chû-tiûⁿ pau-koa tiān-tiûⁿ kap chû-tiûⁿ. Kan-ta chēng-chí ê tiān-hō tō ē tī sì-chiu sán-seng tiān-tiûⁿ, teh tín-tāng ê tiān-hō chiah ē sán-seng chû-tiûⁿ.

Tiān-liû ê pún-chit sī tiān-hō ê liû-tōng.