Txhua chav tsev ntawm lub sijhawm yog qhov tseem ceeb ntawm lub cev kom muaj nuj nqis; microsecond, millisecond, thib ob, feeb, teev, hnub thiab lwm yam.
7 qhov tseem ceeb yog dab tsi?
7 SI base units, uas muaj xws li:
- Length - meter (m)
- Sijhawm - thib ob (s)
- Ntau yam khoom - mole (mole)
- Hluav taws xob tam sim no - ampere (A)
- Temperature - kelvin (K)
- Lim siv zog - candela (cd)
- Mass - kilogram (kg)
Puas yog meter yog ib qho tseem ceeb?
In the International System of Units, the fundamental units are: The meter (symbol: m), used to measure length. Lub kilogram (cim: kg), siv los ntsuas qhov hnyav. Qhov thib ob (cim: s), siv los ntsuas lub sijhawm.
Cov chav hauv paus yog dab tsi?
Hauv SI system, muaj xya qhov tseem ceeb: kilogram, meter, candela, thib ob, ampere, kelvin, thiab mole. Hauv txoj kev xav, ib qho txheej txheem ntawm qhov tseem ceeb (lossis qee zaum qhov loj me) yuav yog qhov uas txhua qhov ntau ntawm lub cev (lossis qhov loj ntawm lub cev muaj nuj nqis) tuaj yeem tsim los ntawm lawv.
Yuav ua li cas units tsis yog qhov tseem ceeb?
S. I chav tsev loj yog kilogram (kg), hos S. I chav rau acceleration yog m/s2. Yog li, S. I unit of force yog kg⋅m/s2. Txij li thaum nws tau nthuav tawm raws li kev sib xyaw ua ke ntawm pawg, qhov ntev, thiab lub sijhawm yog li nws tsis muaj qhov tseem ceeb.
