sheck33 once bubbled...
could you explain the Pound in your beautiful system
The poundforce depends on local value of the acceleration of free fall, the pound mass is a constant
in my universe forces are expressed in Newtons and mass in kilograms, the mass of an object is constant (well semi-constant really unless we refer to an objects restmass when we say 'mass')
these different systems of units are annoying
Following is a direct quote of the conversion factors of pound, poundforce, poundal and their pressure equivilents - - It only remains to be said that in colloqial use - we jsut say pound!
pound (avoirdupois) (lb)23 . . . . . . . . . . . . . . . . . . . . . . . . . . . kilogram (kg) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.535 924 E_01
pound (troy or apothecary) (lb) . . . . . . . . . . . . . . . . . . . . . kilogram (kg) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.732 417 E_01
poundal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . newton (N) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.382 550 E_01
poundal per square foot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pascal (Pa) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.488 164 E+00
poundal second per square foot . . . . . . . . . . . . . . . . . . . . . pascal second (Pa _ s) . . . . . . . . . . . . . . . . . . . . . . . . . . 1.488 164 E+00
pound-force (lbf)24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . newton (N) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.448 222 E+00
pound-force per square inch (psi) (lbf/in2) . . . . . . . . . . pascal (Pa) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.894 757 E+03
pound-force per square inch (psi) (lbf/in2) . . . . . . . . . . kilopascal (kPa). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.894 757 E+00
23 The exact conversion factor is 4.535 923 7 E_01. All units that contain the pound refer to the avoirdupois pound.
24 If the local value of the acceleration of free fall is taken as gn=9.806 65 m/ s2 (the standard value), the exact conversion factor
is 4.448 221 615 260 5 E+00.
sheck33 once bubbled...
these different systems of units are annoying
Agreed! I much prefer metric for anything other than esoteric discussions!
BTW - I haev no intention of getting into a position where I need to measure my restmass or even worry about a markedly different value of g!