Skip to main content
Metrology

Metrology

Why do we want to build a watt balance to determine mass?

21 Sep 2016

When you refer to the mass of something as “10 kg” what you are actually saying? In fact what you mean is that the object in question has a mass equivalent to 10 lots of the platinum-iridium “master kilogram” carefully stored at a bureau just outside Paris. In this video, precision measurement researcher Stephan Schlamminger describes an alternative method for defining a standard kilogram. His proposed approach uses a watt balance which determines mass using fundamental constants as it compares electrical and mechanical power. You can see one of these machines in the video, which Schlamminger presents from the US National Institute of Standards and Technology (NIST) Gaithersburg campus in the US. Schlamminger explains why his method would be advantageous to the existing standard.

This video is part of our 100 Second Science series, in which researchers give concise presentations covering the spectrum of physics.

Related events

Copyright © 2024 by IOP Publishing Ltd and individual contributors