jbriggs444 said:
No es así como funciona el mundo. Uno puede buscar "peso" en un diccionario y encontrar múltiples significados. La palabra es ambigua. Si un escritor desea precisar una palabra para que el uso no sea ambiguo en el contexto, entonces el escritor puede establecer una definición. Si un lector desea comprender el significado, entonces puede buscar una definición local, buscar pistas contextuales o adivinar qué definición de diccionario se aplica.
Si desea utilizar "peso" para referirse a "peso efectivo", dígalo. Todos podemos irnos felices a casa.
Si desea utilizar "peso" para referirse a "fuerza gravitacional", dígalo. Todos podemos irnos felices a casa. Este es un significado que es suficientemente bueno para el aula de física, pero no para la vida real. Con mucho gusto lo adoptaré para un curso en particular si el libro de texto me lo pide.
Si desea utilizar "peso" para referirse a "fuerza gravitacional efectiva en el marco del laboratorio", dígalo. Todos podemos irnos felices a casa. Algunos libros de texto utilizan esta definición. Lo prefiero a la fuerza gravitacional. Este significado hace que el término "ingrávido" sea apropiado.
Si desea utilizar "peso" para significar "masa", dígalo. Todos podemos irnos felices a casa. Este es el significado nominal del comercio en EE. UU.
Si desea utilizar "peso" para referirse a "medición de masa corregida por la gravedad local pero no por la flotabilidad atmosférica", también está bien. Esta es la definición operativa habitual para el comercio y el consultorio médico, al menos en los EE. UU.
Hi all
It is rare to read that, if we are in a science forum we answer as in a science forum, if this were a trade forum, perhaps our definitions would be more lax.
I think that no one can go home happily if they provide five different definitions, saying that it does not matter what they choose and that will be "weight" ... The underlying reasons for the question of why they do it are understood, but they do not have to give us a all the same.
Science defines weight in one way, but when it wants to apply it in everyday life, it presents deviations of the measure, which have nothing to do with "weight", deviations such as the hydrostatic pressure of the air and the rotation of the planet on its Its own axis as a function of latitude are topics that can be discussed and clearly defined, as a result we have that the scales always indicate the value of the normal force of contact with the body that is being measured, this is known as apparent weight.
But the US has nothing to do with how science does science. The US has very good technology but it is 200 years behind by not joining the international system of units. I do not know which idol will fall on the road , or perhaps any other geopolitical reason of the day. The same definition of pound that they use is already expressed in kg, the same "IS" units, so there is nothing logical to wait to join and share units with the rest of the world ... What the US believes to be mass is just that, what the US believes. The rest of us already know what mass and weight are and how to measure them. As I believe that here in the political forum there is no debate, I do not know why it has brought that issue to the thread. Here I leave it.
As commercial scales or scales can only measure weight, it is logical that the law requires that the items be sold by weight, and not by mass, at some point when the moon or Mars is traded perhaps, it is convenient to change that law.
This thread originates, someone wonders why the standards for weight have a unit of measurement in unit of mass.
A logical historical account not faithful to the events, could be made by explaining how science related the atomic number and the atomic mass (measured by comparisons between elements), and tried to establish a relationship between those numerical values and the macroscopic experimental ones, using as a factor conversion of Avogadro's number. But even so, with the definition of meter at that time as the unit of measurement and the second for time, the acceleration of gravity did not result in 1 unit but in 9.81 units, so the force necessary to accelerate a mass of one kg at ##1 m/s^2## it was not equivalent to the same force as to support its weight. That was the moment to decide whether the units of weight were related to the units of mass or the units of mass to the units of weight. The first was decided and today we have the acceleration of gravity and Avogadro's number as conversion factors between the atomic weight of the element with the weight of a body made up of one mole of atoms that single element.
Attempts to establish the kilogram-force
https://en.wikipedia.org/wiki/Kilogram-force did not come to fruition in 1901, and the international system did not adopt it, but it did establish a single unit for force the Newton , which now everyone knows that the weight of a mass of one kilogram on the surface of the Earth in vacuum and without rotation corresponds to ##9.80665 N##.
When that is put into commercial practice, there will be those who take into account or not, what influences the hydrostatic thrust, and the local centripetal force due to the Earth's rotation, to make a fair deal between parties, but that does not change the definition of "weight" as a result of gravitational interaction.
Regards