Do the best you can until you know better. Then when you know better, do better. – Maya Angelou

Mr. Walker's Classroom Blog

The IPK is Actually Older Than I Am!

But it doesn’t matter, it has been replaced with the Kibble balance.



The Kibble balance operated by the US National Institute of Standards and Technology.
Credit: NIST

Of course, it may or may not be a step forward.  Read more about it here in the article on The Atlantic: https://www.theverge.com/2018/11/13/18087002/kilogram-new-definition-kg-metric-unit-ipk-measurement.

Why isn’t this necessarily a step forward?  Why is it?