• Kalash@feddit.ch
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    1 year ago

    Shouldn’t you have come up with something based on water by now that is divisible by 100s?

    Well no, we just adpoted the second in the SI system. The definition it’s not based on water, but caesium.

    The second […] is defined by taking the fixed numerical value of the caesium frequency, ΔνCs, the unperturbed ground-state hyperfine transition frequency of the caesium 133 atom, to be 9192631770 when expressed in the unit Hz, which is equal to s−1

    • jballs@sh.itjust.works
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      1 year ago

      Exactly. Just as every kid learns in kindergarten. A kilogram is the weight of 1,000 cubic cms of water. A liter is the volume of 1 kilogram of water. And a second is the fixed numerical value of the caesium frequency, ΔνCs, the unperturbed ground-state hyperfine transition frequency of the caesium 133 atom, to be 9192631770 when expressed in the unit Hz, which is equal to s−1.