Redefining The Kilogram
Veritasium takes you through the history of the kilogram standard, a block of metal locked in a basement that defines the most important international standard that we have.
Unfortunately, the mass of the current standard is changing thanks to … well, something not entirely known. Atomic evaporation maybe? What is definitely true is that a new kg standard is needed.
The replacement candidate is a nearly perfect sphere of a single isotope of crystalized silicon. It is the world’s roundest object! If this sphere were the Earth, the highest mountain and the lowest valley would only be a few meters apart.
An awesome chemistry and physics lesson from Derek!