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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 nonuniform 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.
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