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Topic: weight and the third law
Replies: 0

 johnreed Posts: 61 Registered: 11/21/09
weight and the third law
Posted: Mar 21, 2012 3:38 PM

Modified Wednesday, March 21, 2012
What does a balance scale measure? What does a spring scale measure?
Most will answer "weight" to both questions. We use each device to
measure weight. We have defined weight [mg] mathematically consistent
with the least action consistent natural motion in the universe. The
spring scale does measure weight [mg]. It is calibrated to do that at
location and requires recalibration at a change in location.

The balance scale does not measure weight. The balance scale compares
two pans of matter where [g] in [mg] acts globally on the scale and
contents such that the scale will, once calibrated to balance, balance
at any location where it can be used. Using the product [mg] for
weight the balance scale compares mass only.

We use both devices to measure weight. In the simplest case the spring
stretches or is compressed by the weight [mg] of an object acting on
it. A dial or guage provides us a reading for weight [mg]. The
balance scale only compares mass [m] because [g] acts on everything in
the area the same.

It is convenient to measure atoms in terms of weight. This is what we
work against. It is not fundamental. It is convenient to measure
weight in terms of mass. It is not fundamental to the actual physical
act of attraction. It is fundamental to calculate the force we must
apply at location [g].

The planet attractor does not act on mass. The planet attractor acts
uniformly on non-uniform atoms. Nonetheless mass is a useful quantity
to us and it is fortunate that it is conserved consistent with the
measure of resistance of the number and type of atoms it represents.

Consider a pure element consisting of only one isomer. On a balance
scale, imagine that we can place one atom at a time in a pan. We have
a standard object calibrated in mass units in the other pan. We can
(theoretically) place one atom at a time in one pan until it is
balanced against the standard mass in the other pan. When we lift
either the pan with atoms or the pan with the standard mass we feel
weight. We feel the product [mg] at location [g]. We feel at location
[g], the cumulative resistance (mass) of the number of atoms in the
pure object pan at that location.

In this example the balance scale compares the resistance of a
quantity of atoms to the resistance of a quantity of matter calibrated
in mass units. Each atom in the pure object pan is uniformly acted
upon by the planet attractor.

Is this uniform action on each atom a consequence of each atom being
identical in the pure object? Or is it a consequence of the planet
attractor?s uniform action on atoms in general?

The number of atoms in each pan need not be the same. In the pure atom
pan we are measuring the cumulative resistance of the number of atoms.
We know this because we watched the process itself. Let's say we call
this cumulative resistance ?mass?, because we are measuring the
cumulative comparative resistance of atoms in the pure object pan
against the object in the pan calibrated in mass units.

Side bar question for extra credit. Is the mass of the calibrated
object also the cumulative resistance of the atoms in that object?
Explain your reasoning to yourself. Or in a written reply to this
post, if you wish.

When we define mass in terms of a number of atoms, the occult aspect
of equal and opposite forces between planet surface objects and
planets vanish. In fact the equal and opposite law must be
rewritten. The force we feel and/or apply is equal to the resistance
we encounter [F=mg] and [F=ma]. This by definition. The resistance of
a planet surface object when defined in terms of weight and quantified
in terms of a number of atoms can hardly be set equivalent to the
resistance of the atoms composing the planet. It is equivalent to the
resistance we measure and work against.