Yesterday on the 20th of May 2019, the definition of a kilogram changed. It used to be represented by "Le Grand K" located in a triple-locked vault underneath the Pavillon de Breteuil. It is a unit that weighs roughly 2.2 pounds. The metric system has been to changed to avoid possible complications due to physical changes with "Le Grand K". The new definition of a kilogram will most likely stay the same till the end of time. The kilogram is now equal to the weight of 1.4755214 x 1040 photons with frequencies matching a cesium atomic clock. This sounds complicated and is actually more complicated, but at least it's more accurate. The main difference is that the new variable is constant unlike a solid object that would be influenced by air particles (and anything else that exists).
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