Standard - Changes in the Definition of the Metric System (1)

It's the name of the international standard system of measurement, and it's also called the SI unit, taking the abbreviation from French, which had the strongest influence when the metric system was established. The metric system defines a total of 7 units of measurement. Second, Meter, Kilogram, Ampere (electric current), Kelvin (temperature), Mole (amount of substance), Candela (luminous intensity) However, significant errors were found in the initial definition, so the standard was recently changed and redefined. This is because if we were to adhere to the original definition, the familiar units of measurement currently in use would have to be completely changed. Therefore, we chose to keep the currently used units of measurement and redefine them based on a standard that will never change. The current redefined standard involves overly long numerical notations, so only the standard will be presented, and the exact numbers will not be shown. 1. Second Initial Definition: 1/86400 of the Earth's one rotation period (a day) Current Definition: Redefined based on the frequency of Cesium-133 Reason for Change: The Earth's rotation period is slightly slowing down due to the Moon's gravitational pull. (This was explained in the explanation of synchronous rotation)