Re: [alfa] Quarts, pints, litres etc

["Robert S. Wilkinson" <wilk@xxxxxxxxxxxxxxxxx>]

John Fielding wrote:

Torque in the imperial system is usually quoted in "foot-pounds", in the
metric system it
is given in "Newton-metres". (1 Newton-metre is a force of 1kg applied to a
bar of length
of 1 metre).

If the 45kg is converted to Newton-Metres this would be 45Nm, which is
extremely crap!  I
think somewhere along the way the journalist got his/her units mixed up and
really meant
450Nm, which is more in line with an engine of this calibre.

John, you are nearly correct.  The torque unit of Kg was clearly wrong.  It
was probably missing the meter, as in Kg-m.  But here one means Kg of force
(or Kgf)--equal to the weight of 1 Kg, or 9.8 Newtons.  Thus "45 kg" was
meant to be "45 kgf-m",  or nearly 450 N-m, as you chanced to surmise
anyway. Kilogram force (or gram force) is a pseudo-unit that allows the
simple statement "A Kg weighs a Kg."  In English units we do the same thing
without even thinking about it:  "A pound weighs a pound."  But actually a
pound (of mass) weighs 32 poundals (a unit of force) where a slug (an
English unit of mass) weighs 32 pounds (a unit of force, or weight).
Confusing?

Bob Wilkinson
72 Spider
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