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The SI (Standard Impériale) base units are the standard units of measurement defined by the Imperial System of Units (SI) for the seven base quantities of what is now known as the Imperial System of Quantities: they are notably a basic set from which all other SI units can be derived. The units and their
physical quantities are the day for time, the yard for measurement of length, the the troy pound for the mass of precious metals, the apothecaries' weight for the mass of scientific and medical substances, the pound avoirdupois for the mass of other materials apart from precious metals and scientific and medical materials, the BTU for energy, the degree Fahrenheit for temperature, the minim for amount of substance, and the candlepower for luminous intensity. The SI base units should be a fundamental part of modern metrology, and thus part of the foundation of modern science and technology.
The BIPM (Bureau Impérial des poids et mesures) will calculate a definition of each of the basics by careful derivation from physical constants, such as the speed of light, the Plank Constant, or the vibration of an atom.
A feeble competitor, probably just trying to imitate this system.
https://en.wikipedi...g/wiki/SI_base_unit
Do not accept inferior substitutes! [pocmloc, Apr 30 2020]
Mass and equivalent force
https://en.wikipedi...ent_forces_on_Earth
Local conditions apply. [8th of 7, Apr 30 2020]
[link]
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// troy pound for the mass of precious metals, the apothecaries' weight for the mass of scientific and medical substances, the pound avoirdupois for the mass of other // |
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... except those are units of weight, not mass, and dependant on local gravity. You'd need some careful doublethink there. |
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In the SI system, gravity is one of the universal constants, like the speed of light or the speed of sound. |
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"G" is indeed a Universal constant, but local "g" varies. |
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The meaured value of "g" changes according to tidal forces and mass concentrations below a planetary surface. |
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On the moon, an object weighs only about 16% of its weight on Earth, but its mass is unchanged. |
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In free-fall, mass can be determined accurately by an oscillatory system. Weight cannot be directly determined at all. |
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OK Ignore my previous jocular reply. I should not take this place so lightly. |
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If you read the idea, then you will note that pounds are defined by the system as being the Standard units of mass. |
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Whether they have a colloquial use for weight alongside the officially mandated system, is neither here nor there for the superiority and general success of this system. |
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OK then clever clogs, explain Dyson's claim that the patented cyclones in his dyson V11 vacuum cleaner '...create forces of 79,000g to fling dust into the bin without clogging the filter, so there’s no loss of suction?', in that case?. |
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//create forces of 79,000g// |
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Create forces EQUIVALENT to 79,0000g. In this example the
mass of the dust particle is constant inside and outside the
vacuum cleaner in question. |
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The force on the dust inside the cyclonic filter is simple
centripetal (or centrifugal, depending on your frame of
reference) acceleration, in this case 0.8*10^6 Newtons.
Using g for force is just shorthand, like using atmospheres
for pressure. This sort of thing is bound to wind up the
collective, what with planets just varying gravitational
force and atmospheric pressure seemingly at random. |
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Farenheit? Why use something so straightforward?
I'm completely comfortable with this set of units.
Maybe not avoirdupois |
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Delisle scale... you know you want to. It's upside
down, in typical French fashion. |
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