Txoj Cai Coulomb

Hauv tsab xov xwm txog nqi hluav taws xob dan hom nqi hluav taws xob Piav qhia tias cov hluav taws xob zoo li cov hluav taws xob sib tsoo thaum cov hluav taws xob sib tsoo. Hauv lwm lo lus, cov khoom muaj zog zoo rub cov khoom muaj zog tsis zoo, cov khoom muaj zog zoo thawb cov khoom muaj zog zoo, thiab cov khoom muaj zog tsis zoo thawb cov khoom muaj zog tsis zoo. Qhov xwm txheej no qhia tau tias muaj lub zog hluav taws xob ua rau cov khoom muaj zog zoo thiab cov khoom muaj zog tsis zoo. Dab tsi yog cov yam ntxwv uas cuam tshuam rau qhov loj ntawm lub zog hluav taws xob ntawm cov khoom muaj zog hluav taws xob?

Tus kws tshawb fawb Fabkis Charles Coulomb (1736–1806) tau ua ntau yam kev sim hauv xyoo 1780 los tshawb nrhiav cov yam ntxwv uas cuam tshuam rau qhov loj ntawm lub zog hluav taws xob ntawm cov khoom uas muaj hluav taws xob. Lub cuab yeej uas Coulomb siv zoo ib yam li lub uas Cavendish siv los tshawb nrhiav qhov sib npaug ntawm lub ntiajteb txawj nqus, hu ua qhov sib npaug torsion. Coulomb tshawb nrhiav lub zog hluav taws xob, yog li ntawd nws siv ob lub pob hlau uas muaj hluav taws xob, thaum Cavendish tshawb nrhiav lub zog gravitational, yog li ntawd nws siv ob lub pob uas tsis muaj hluav taws xob.

Yuav ua li cas lub torque scale ua haujlwm  

 
Yuav ua li cas lub torque scale ua haujlwm muaj feem cuam tshuam nrog cov ntsiab lus torque los yog lub zog ntawm lub zog nyob rau hauv tshooj kev hloov pauv ntawm lub zog.
Qhov chaw nyob hauv qhov sib npaug torsion yog qhov chaw nqus tsev kom tiv thaiv cov hluav taws xob ntawm lub pob khov kho kom tsis txhob hloov mus rau huab cua. Kev txiav txim siab ntawm qhov ntau ntawm cov hluav taws xob ntawm lub pob khov kho yog ua tiav los ntawm kev siv txoj kev hauv qab no. Thaum pib, lub pob khov kho A yog ua hluav taws xob los ntawm kev sib txuas lossis kev sib txhuam. Lub pob khov kho A uas tau raug hluav taws xob raug txuas nrog lub pob khov kho B uas tseem tsis muaj zog siv tus neeg coj hluav taws xob kom txog thaum cov hluav taws xob ntawm lub pob khov kho A raug faib sib npaug nrog lub pob khov kho B. Yog tias qhov ntau ntawm cov hluav taws xob ntawm lub pob khov kho A yog ½ ces qhov ntau ntawm cov hluav taws xob ntawm lub pob khov kho B yog ½. Tom ntej no, lub pob khov kho B thiab lub pob khov kho C raug txuas nrog tus neeg coj hluav taws xob kom txog thaum cov hluav taws xob ntawm lub pob khov kho B raug faib sib npaug nrog lub pob khov kho C. Yog tias qhov ntau ntawm cov hluav taws xob ntawm lub pob khov kho B yog ¼ ces qhov ntau ntawm cov hluav taws xob ntawm lub pob khov kho C yog ¼. Qhov ntau ntawm cov hluav taws xob thiab hom hluav taws xob ntawm lub pob khov kho 1 thiab lub pob khov kho 2 tau txais los ntawm txoj kev no.

Lub pob zeb khov kho 1 thiab lub pob zeb khov kho 2 muaj hluav taws xob them kom ob lub pob zeb khov kho sib tawm tsam yog tias ob lub pob zeb muaj tib lub nqi hluav taws xob lossis rub ib leeg yog tias ob lub pob zeb muaj cov nqi hluav taws xob sib txawv. Qhov muaj lub zog nyiam lossis lub zog tawm tsam ntawm ob lub pob zeb khov kho uas muaj hluav taws xob them ua rau lub pob zeb khov kho 2 tig. Lub kaum sab xis ntawm kev mus ncig ntawm lub pob zeb khov kho 2 raug ntsuas los txiav txim siab lub zog hluav taws xob ua rau ob lub pob zeb khov kho.

Cov yam tseem ceeb uas cuam tshuam rau lub zog hluav taws xob

Raws li kev sim ua los ntawm kev siv lub torsion balance, Coulomb tau tshawb pom ntau yam.
– Hauv qhov kev sim no, qhov deb ntawm ob lub pob khoom khov kho yeej ib txwm zoo ib yam. Thaum qhov ntau ntawm cov nqi hluav taws xob ntawm lub pob khoom khov kho 1 yog 1 thiab qhov ntau ntawm cov nqi hluav taws xob ntawm lub pob khoom khov kho 2 yog 1 ces lub zog hluav taws xob ua rau ob lub pob khoom khov kho yog 1. Thaum qhov ntau ntawm cov nqi hluav taws xob ntawm lub pob khoom khov kho 1 yog 2 thiab qhov ntau ntawm cov nqi hluav taws xob ntawm lub pob khoom khov kho 2 yog 2 ces lub zog hluav taws xob ua rau ob lub pob khoom khov kho yog 4. Coulomb xaus lus tias qhov loj ntawm lub zog hluav taws xob ua rau ob lub pob khoom khov kho yog proportional rau cov khoom ntawm qhov ntau ntawm cov nqi hluav taws xob ntawm ob lub pob khoom khov kho (F ≈ q₁ q₂).
– Hauv qhov kev sim no, qhov ntau ntawm cov nqi ntawm ob lub pob khoom khov kho yeej ib txwm zoo ib yam. Yog tias qhov deb ntawm ob lub pob khoom khov kho yog 1 ces lub zog hluav taws xob ua rau ob lub pob khoom khov kho yog 1. Yog tias qhov deb ntawm ob lub pob khoom khov kho yog 2 ces lub zog hluav taws xob ua rau ob lub pob khoom khov kho yog ¼. Coulomb xaus lus tias qhov loj ntawm lub zog hluav taws xob ua rau ob lub pob khoom khov kho yog inversely proportional rau lub square ntawm qhov deb (F ≈ 1 / r²)

Txoj Cai Coulomb

Txoj cai Coulomb yog ib txoj cai ntawm physics uas piav qhia txog kev sib raug zoo ntawm lub zog hluav taws xob, lub zog hluav taws xob, thiab qhov deb ntawm cov nqi hluav taws xob. Txoj cai no tau tsim los ntawm Coulomb cov kev sim, raws li tau piav qhia hauv tsab xov xwm dhau los.

Txoj Cai Coulomb hais tias qhov loj ntawm lub zog uas ib lub khoom me me uas muaj hluav taws xob siv rau lwm lub khoom me me uas muaj hluav taws xob yog sib npaug ncaj qha rau cov khoom ntawm qhov sib npaug ntawm cov nqi ntawm ob lub khoom me me thiab sib npaug rov qab rau lub xwmfab ntawm qhov deb ntawm ob lub khoom me me uas muaj hluav taws xob. Lub zog no ua raws li txoj kab ncaj nraim txuas ob lub khoom me me. Lub zog hluav taws xob yog qhov tsis zoo yog tias cov nqi hluav taws xob ntawm ob lub khoom me me zoo ib yam thiab lub zog hluav taws xob nyiam yog tias cov nqi hluav taws xob ntawm ob lub khoom me me tsis zoo ib yam.

Txoj cai Coulomb tuaj yeem qhia tau hauv cov lej lej:
Kev piav qhia txog cov mis:
F₁₂ = lub zog hluav taws xob ntawm cov khoom me me 1 thiab cov khoom me me 2
q₁ = tus naj npawb ntawm cov nqi particle 1
q₂ = tus naj npawb ntawm cov nqi hluav taws xob ntawm cov khoom me me 2
r₁₂ = qhov deb ntawm cov khoom me me 1 thiab cov khoom me me 2
(nyeem: epsilon xoom) = 8,854 x 10^-12 C²/Nm²
k = (Coulomb tus nqi tas mus li) = 9 x 10⁹ Nm²/C²
F₂₁ yog lub zog uas them los ntawm q₂ ntawm lub zog q₁, thaum F₁₂ yog lub zog uas them los ntawm q₁ ntawm lub zog q₂. F₂₁ thiab F₁₂ sib ntaus sib tua thaum lub zog yog q₁ thiab q₂ zoo sib xws thiab rub ib leeg thaum lub nqi yog q₁ thiab q₂ tsis yog tib hom.
F₂₁ thiab F₁₂ muaj tib lub nqi, kev taw qhia sib txawv thiab ua rau cov khoom sib txawv, yog li ntawd ob lub zog no yog ib khub zog ua-ua haujlwm.