If these devices determine an objects mass, then shouldn't they properly be called a balance? A scale is used to measure weight (in the sense of force) and not mass.
An electronic scale measures force just like a spring scale. It is affected by gravitation, just like a spring scale, and unlike a balance scale.
The vast majority of common (household) uses of scales are for mass, not for force: mass of food on a kitchen scale, mass of your body on a bathroom scale, carrying capacity of a trailer, etc. This is part of why I think it is counter-productive to try to get people to say "mass" rather than "weight" when they are using grams and scales.
It is not easy to come up with a true "force" measurement in common (household) use. I've thought of the breaking strength of fishing line (or rope), but that's about it.
This is NOT to say that we should ignore the distinction, and allow "kilogram-force" to come into usage. But when you are weighing a food portion, you are not concerned with force, you are concerned with mass, and I think saying "weigh" and "weight" is perfectly fine.
Jim Elwell, CAMS Electrical Engineer Industrial manufacturing manager Salt Lake City, Utah, USA www.qsicorp.com
