Cov lus teb, yooj yim, yog qhov thib ob yog 1/60th ntawm ib feeb, lossis 1/3600th ntawm ib teev.
1 thib ob yog dab tsi?
Qhov thib ob txhais tau tias yog sib npaug rau sijhawm sijhawm ntawm 9, 192, 631, 770 lub sijhawm ntawm cov hluav taws xob sib txuas rau kev hloov pauv ntawm ob theem hyperfine ntawm lub hauv paus unperturbed av-xeev ntawm caesium-133 atom.
txhais li cas thib ob?
Definition. Qhov thib ob yog txhais los ntawm noj tus lej tas li ntawm cesium zaus ∆ν, qhov tsis muaj kev cuam tshuam hauv av-xeev hyperfine hloov pauv zaus ntawm cesium 133 atom, yuav yog 9 192 631 770 thaum hais hauv unit Hz, uas yog sib npaug rau s −1
Puas muaj pes tsawg feeb hauv ib pliag?
Vim muaj 1 feeb hauv 60 vib nas this, muaj 160 feeb hauv 1 thib ob.
Dab tsi ua rau lub sijhawm thib ob?
Ib pliag yog lub sijhawm uas dhau mus thaum lub sijhawm 9, 192, 631, 770 (9.192631770 x 10 9) cycles ntawm cov hluav taws xob tsim los ntawm kev hloov pauv ntawm ob theem ntawm cesium 133 atom… Qhov no yooj yim muab los ntawm qhov tseeb tias muaj 60 vib nas this hauv ib feeb, 60 feeb hauv ib teev, thiab 24 teev hauv ib hnub hnub ci.
