3 ms·
It's defined in terms of other units.
by snet0 5y ago
It's defined in terms of other units.
- snet0 5y agoOf course, once you get to the second, we are now just measuring something, and our unit is based on counting a thing. But how do you measure something that can't be counted?
- cbmuser 5y agoIt’s an SI unit and directly defined through the speed of light which is a universal constant number. While you need „second“ to define the „meter“, the former is not derived from other units but from an observation of nuclear reactions in Caesium.
- alentist 5y agoSI units are now defined directly in terms of physical laws (no prototypes needed). https://en.wikipedia.org/wiki/2019_redefinition_of_the_SI_base_units https://en.wikipedia.org/wiki/2019_redefinition_of_the_SI_ba...