What exactly is "exact" (was Clean Singleton Docstrings)

[Ian Kelly]

On Tue, Jul 19, 2016 at 2:35 PM, Gene Heskett <gheskett at shentel.net> wrote:
> And I am not familiar with this foot-poundals per second that you
> question about, but just from the wording I'd say it is a fifty dollar
> way to say horsepower.

https://en.wikipedia.org/wiki/Foot-poundal

> Which is defined in the area of exerting a force
> to a 440 pound weight, sufficient to lift that weight one foot in one
> second.

1 (imperial) horsepower is 550 (not 440) foot-pounds per second. A
foot-pound is the energy transferred by exerting a 1-pound force
through a displacement of 1 foot. A pound is the force needed to
accelerate 1 pound-mass at 32.174 ft/s**2 (the acceleration of
gravity). A poundal in contrast is the force needed to accelerate 1
pound-mass at 1 ft/s**2. A foot-poundal therefore is the energy
transferred by exerting a 1-poundal force through a displacement of 1
foot. A foot-poundal is thus (approximately) 1/32.174 of a foot-pound.

Multiplying it out, 1 horsepower is approximately 17695.7
foot-poundals per second.

Ah, the machinations that users of imperial units have to endure.