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From: glird on 1 Aug 2010 13:12
Since a force is a net pressure, and the textbooks say that weight
is a force, a gram is a unit of weight and force. Another unit of
force is a dyne. The textbook definition of a dyne is “a ‘dyne’ is
that force which will produce an acceleration of 1 cm per second per
second when acting on a mass of 1 gram". ("Mass" denotes a quantity of
matter. As such, it too is a dimension.)
Though the quantity of atomic matter in different bodies is
proportionate to their respective weight, unstructured matter [now
called "dark matter"] has no weight. A gram, however, is a quantity of
weight, which is a force. Therefore a gram and an ounce are the wrong
units of measure for a quantity of matter!
From: dlzc on 1 Aug 2010 15:44
Dear glird:

On Aug 1, 10:12 am, glird <gl...(a)aol.com> wrote:
>   Since a force is a net pressure,

No, pressure is a force distributed over an area.

> and the textbooks say that weight is a force,

Some textbooks. It takes a force to restrain a weight, to keep it
from moving inertially.

> a gram is a unit of weight and force.

No, it is a unit of mass.

> Another unit of force is a dyne.
> The textbook definition of a dyne is “a
> ‘dyne’ is that force which will produce an
> acceleration of 1 cm per second per
> second when acting on a mass of 1 gram".
> ("Mass" denotes a quantity of matter. As such,
> it too is a dimension.)
>   Though the quantity of atomic matter in
> different bodies is proportionate to their
> respective weight, unstructured matter [now
> called "dark matter"] has no weight.

It appears to be gravitationally bound, yet it cannot be restrained,
so that its weight cannot be ascertained.

> A gram, however, is a quantity of weight,

Mass, not weight. Weight depends on a local value of g.

> which is a force. Therefore a gram and an
> ounce are the wrong units of measure for a
> quantity of matter!

http://physics.nist.gov/cuu/Constants/index.html

You've been drinking again, haven't you?

David A. Smith
From: harald on 2 Aug 2010 02:37
On Aug 1, 7:12 pm, glird <gl...(a)aol.com> wrote:
>   Since a force is a net pressure, and the textbooks say that weight
> is a force, a gram is a unit of weight and force.  Another unit of
> force is a dyne. The textbook definition of a dyne is “a ‘dyne’ is
> that force which will produce an acceleration of 1 cm per second per
> second when acting on a mass of 1 gram". ("Mass" denotes a quantity of
> matter. As such, it too is a dimension.)
>   Though the quantity of atomic matter in different bodies is
> proportionate to their respective weight, unstructured matter [now
> called "dark matter"] has no weight. A gram, however, is a quantity of
> weight, which is a force.  Therefore a gram and an ounce are the wrong
> units of measure for a quantity of matter!

In addition to dlzc: for "weight" some old books used kgf, thus the
force that 1 kg of mass exerts on earth.
1 kgf = 9.8 N - not to be confused with 1 kg!

Harald
From: dlzc on 2 Aug 2010 10:19
Dear harald:

On Aug 1, 11:37 pm, harald <h...(a)swissonline.ch> wrote:
> On Aug 1, 7:12 pm, glird <gl...(a)aol.com> wrote:
>
> >   Since a force is a net pressure, and the
> > textbooks say that weight is a force, a gram
> > is a unit of weight and force.  Another unit
> > of force is a dyne. The textbook definition
> > of a dyne is “a ‘dyne’ is that force which
> > will produce an acceleration of 1 cm per
> > second per second when acting on a mass of 1
> > gram". ("Mass" denotes a quantity of matter.
> > As such, it too is a dimension.)
> >   Though the quantity of atomic matter in
> > different bodies is proportionate to their
> > respective weight, unstructured matter [now
> > called "dark matter"] has no weight. A gram,
> > however, is a quantity of weight, which is a
> > force.  Therefore a gram and an ounce are
> > the wrong units of measure for a quantity of
> > matter!
>
> In addition to dlzc: for "weight" some old
> books used kgf, thus the force that 1 kg of
> mass exerts on earth.
> 1 kgf = 9.8 N - not to be confused with 1 kg!

http://www.engineeringtoolbox.com/unit-converter-d_185.html#Pressure
(there is a popup if you click the link, sorry)
.... theck out these units of pressure:
kg/m^2, gram-force/sq cm, kg-force/sq cm, equating 1 psi to 16 ounces,
and so on. Looks like "glird" is not the only one drinking...

David A. Smith
From: harald on 2 Aug 2010 12:44
On Aug 2, 4:19 pm, dlzc <dl...(a)cox.net> wrote:
> Dear harald:
>
> On Aug 1, 11:37 pm, harald <h...(a)swissonline.ch> wrote:
>
> > On Aug 1, 7:12 pm, glird <gl...(a)aol.com> wrote:
>
> > >   Since a force is a net pressure, and the
> > > textbooks say that weight is a force, a gram
> > > is a unit of weight and force.  Another unit
> > > of force is a dyne. The textbook definition
> > > of a dyne is “a ‘dyne’ is that force which
> > > will produce an acceleration of 1 cm per
> > > second per second when acting on a mass of 1
> > > gram". ("Mass" denotes a quantity of matter.
> > > As such, it too is a dimension.)
> > >   Though the quantity of atomic matter in
> > > different bodies is proportionate to their
> > > respective weight, unstructured matter [now
> > > called "dark matter"] has no weight. A gram,
> > > however, is a quantity of weight, which is a
> > > force.  Therefore a gram and an ounce are
> > > the wrong units of measure for a quantity of
> > > matter!
>
> > In addition to dlzc: for "weight" some old
> > books used kgf, thus the force that 1 kg of
> > mass exerts on earth.
> > 1 kgf = 9.8 N - not to be confused with 1 kg!

> http://www.engineeringtoolbox.com/unit-converter-d_185.html#Pressure
> (there is a popup if you click the link, sorry)
> ... theck out these units of pressure:
> kg/m^2, gram-force/sq cm, kg-force/sq cm, equating 1 psi to 16 ounces,
> and so on.  Looks like "glird" is not the only one drinking...
>
> David A. Smith

Dear David, thanks for the reference. Under "force":

"1 N (Newton) = 1/9.80665 kgf" => 1 kgf = 9.80665 N.

Looks indeed like "glird" is not the only one drinking! ;-)

Cheers,
Harald
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