SI prefixes (International System of Units) yog siv los txheeb xyuas qhov loj thiab me me dhau ntawm lub cev. Cov prefixes no tau muab tso ua ntej cov cim sib thooj ntawm qhov ntau hauv physics. Xav txog hauv kab lus nquag siv ua ntej, lawv lub ntsiab lus thiab cov npe.
SI prefixes hauv physics yog dab tsi?
Nyob rau hauv SI system, International Chamber of Weights and Measures qhia prefixes rau qhov tseem ceeb ntawm lub cev muaj nuj nqis, uas muaj nyob rau hauv cov lus hauv qab no.
Cov lus qhia ua ntej no yog siv ntau tshaj plaws. Muaj lwm tus - nrog ntau dua thiab tsawg dua qib. Yog li, qhov tsawg tshaj plaws prefix yog yocto (y) - 10 -24, thiab qhov loj tshaj plaws yog iota (Y) - 10 24.
Yog li, SI prefixes cover values from 10-24 to 1024. Txij li qhov ntau hauv physics tuaj yeem muaj qhov loj thiab me me, nws tsis yooj yim siv lawv yog tias lawv tau hais hauv cov chav SI yooj yim. Rau cov xwm txheej no, prefixes yog siv. Piv txwv li, atmospheric siab nyob rau saum npoo ntawm peb ntiaj chawyog kwv yees li 100,000 Pa, feem ntau tus nqi no yog sau li 100 kPa (kilopascal) los yog li 0.1 MPa (megapascal).
Siv prefixes
Kev siv SI ua ntej yog ua raws li cov cai hauv qab no:
- Koj tsis tuaj yeem sau ob lub npe ua ke, piv txwv li, 10-9 m tsis tuaj yeem sau ua 1 µm (micromillimeter), tab sis yuav tsum sau ua 1 nm (nanometer).
- Yog tias lub cev muaj nuj nqis hauv nws qhov kev xaiv muaj qib thiab cov npe ua ntej, ces koj yuav tsum xub coj mus rau hauv tus account lub npe ua ntej, piv txwv li km2 - square kilometers.
nquag siv ua ntej rau cov khoom sib xws
Txoj kev xav, tag nrho SI prefixes tuaj yeem siv nrog txhua lub cev, tab sis kev lig kev cai, tsuas yog qee qhov ntawm lawv siv nrog qee qhov ntau. Cov hauv qab no yog ntau lub cev thiab cov lus ua ntej uas feem ntau siv nrog lawv.
- Maj. Nws feem ntau qhia hauv milligrams, kilograms, micrograms. Rau cov loj loj, units xws li megagrams thiab gigagrams yuav luag tsis siv, es tsis txhob ntawm lawv lawv siv tons, uas cov prefixes twb tau siv, piv txwv li, megaton.
- Vaj. milliliter, microliter, cubic kilometers, cubic decimeter yog lub ntsiab prefixes rau tus nqi no.
- Length. Txhawm rau ntsuas nws, mais, decimeters, centimeters, millimeters thiab me dua units yog siv. Raws li nrog ntim, megameters thiab gigameters tsis siv. Rau kev siv mus ntevastronomical quantities, xws li parsec.
- Sijhawm. Millisecond, microsecond thiab me prefixes feem ntau yog siv los qhia lub sijhawm. Lub sijhawm luv luv yog ntsuas hauv cov xuab moos thiab lub ntiaj teb xyoo, thaum cov units ntawm megasecond thiab gigasecond tsis tshua siv.
