Originally posted by Class A Are you sure that you saw the weight of something being specified rather than its mass?
Since gravitational mass and inertia mass are equivalent, one can measure the mass of something by weighing it (and converting considering the gravitational field).
A scale for body weight on earth is not intended to report the force that your body produces in earth's gravitational field, but the mass of your body. Hence the unit used is "kg" not "N".
I suspect that in all your observations the unit "kg" is correctly used to express the mass of something.
The imprecision is only in everday language where people do not consider other gravitational fields (e.g., that on the moon) and therefore do not distinguish between weight and mass. That unawareness of the difference between these concepts probably exists just as much in countries that do not use metric systems, if only through lay people pretty much never using the unit for mass.
They use Newton-meter, of course, since only a force is involved.
Kilogram-meter, would only make sense if the force were created by a mass, which is typically not the case.
In my early university career, we still worked in the Imperial System of units, which was confounding to some in these matters. The lengths people went to, to rationalise the system, was quite baffling to the layperson, so it's no wonder there's still confusion abroad. If you've never heard of a poundal, and you don't have anything better to do,
then look it up.
In a similar vein, there was an early attempt to rationalise the MKS System (pre-SI) and there was such a unit as the kilogram-force recognised in it. It was the force generated when accelerating one kilogram mass at 9.81 ms-2 (in other words, 9.81 N), but in order to distinguish it from a kilogram-mass, the subscript "f" was added to it. Sloppy people left that off, leading to further confusion and ultimately to the banning of its use in accredited tertiary programs.
Don't get me started on British Thermal Units...