Why don't more people use Newton's Second Law conversion factor ( gc ) ? Use of gc makes it much easier to keep track of units in problems.?

in chemical engineering, gc is the unit factor formed from this relationship.

.. 1 lbf = 32.174 lbm ft / s²

so that

.. gc = (32.174 lbm ft / s²) / (1 lbf)

it is simply a conversion factor.

These days, instead of teaching gc (which we call "g sub c" in the ChE world), we teach factor label method for unit conversion and we teach students how and where to look up those conversion factors and how to use them to solve problems.

for example..

.. convert 100lbm resting on an area of 10 in² on the surface of the moon to lbf in psi.

solution

.. (100lbm / 10in²) x (1lbf / 32.174 lbm ft / s²) x (1.622m / s²) x (3.28 ft / m) = 1.65 psi

clean straightforward consistent method. vs.. well.. you tell me how you would do that conversion with gc.

*******

gc has actually been dropped from many of the ChE textbooks (elementary principles of chemical processes.. felder and rousseau.. for example) and replaced with factor label method. But even so, many of the old die hard ChE's using British units still like to use gc.

*******

btw... I showed the examples in American engineering units... but the SI or cgs units have the same gc.

.. 1N = 1kg m / s² ===> gc = 1kgm/s² / 1N

and the examples work out the same

Time is not the case in this world.