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Why does current flow the opposite way from the electrons?

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Re: Why does current flow the opposite way from the electrons?

#171

Post by adrian_b »

lupire wrote: post #142
adrian_b wrote: post #125

Earlier quoted context omitted.

The reason why which charge is named positive and which is named negative does not matter is because in all the equations that relate electric charge with other measurable physical quantities we never have an electric charge alone, but we always have the product of two electric charges. The value of the product of two electric charges is invariant to the convention chosen for the sign of the electric charge. Numbers…

Numbers do not exist in the world. Umbers exist outside the world.

I do not know if this is a joke about shadows that I did not get, or just a typo, but numbers exist in the world.

The world is composed of things. The things are grouped in sets. Numbers are equivalence classes of sets.

The set of the medium-sized planets of the Solar System is equivalent in number with the set of the big planets of the Solar System and also equivalent in number with the set of the big satellites of Jupiter (i.e. 4).

Such equivalences between sets of things exist regardless if there are any sentient beings that recognize those equivalences and there are circumstances when for instance the evolution in time of some sets of things is determined or influenced by the relationship between the numbers of things that compose each set.

Re: Why does current flow the opposite way from the electrons?

#172

Post by lloeki »

ArnoVW wrote: post #140
mrunkel wrote: post #94

Earlier quoted context omitted.

In German we use “Akku” which is short for “Akkumulator” for rechargeable batteries.

Or ‘pile’ in French, which is homonym for ‘stack’ because a battery is a stack of alternating materials.

interestingly "accu" in french is also used, but only for rechargeable batteries.

Re: Why does current flow the opposite way from the electrons?

#173

Post by shepherdjerred »

SoftTalker wrote: post #157
wongarsu wrote: post #124

Earlier quoted context omitted.

Yes. If you have an electrical network that isn't grounded anywhere you can't get a shock from touching only one wire because there wouldn't be any current flow. If you repair electronics you might do that to a single device with an isolating transformer, or if you are a hospital you might do that to the entire building. But at the scale of a national grid it's basically impossible to ensure that the entire grid is i…

The commonplace example of this would be a battery, correct? You can touch + or - separately and feel nothing.

I thought that was safe because the voltage/current isn't enough to go through skin or something like that.

Re: Why does current flow the opposite way from the electrons?

#174

Post by adrian_b »

bithive123 wrote: post #165
adrian_b wrote: post #125

Earlier quoted context omitted.

The reason why which charge is named positive and which is named negative does not matter is because in all the equations that relate electric charge with other measurable physical quantities we never have an electric charge alone, but we always have the product of two electric charges. The value of the product of two electric charges is invariant to the convention chosen for the sign of the electric charge. Numbers…

Negation, being a concept, exists only in the mind. Same with "things". A thing is a noun; a part of speech. The "real world" is undifferentiated quanta.

While in the mathematics of the later part of the 19th century and of the 20th century there have been developed many theories with very abstract concepts for which it may be claimed that those concepts have been invented in the minds of some mathematicians without a direct correspondence with the world experienced by them, such a claim would be false about almost any concept in the mathematics developed until the 19th century, because almost all older mathematical concepts are just abstractions of properties of the physical world.

For instance, what happens when you connect the two electrodes of a battery to the pins of a semiconductor diode will differ depending on whether you negate the battery or not (i.e. you revert or not its connections). What happens with a ball (or with a thrown stone) will differ depending on whether its velocity is positive or negative, and so on.

Additions and subtractions of physical quantities, therefore also negation, happen in the physical world regardless of the presence of sentient beings.

Humans can recognize such properties of the world and give them names and integrate them in coherent mathematical models, but the base concepts are not inventions, they are the result of empirical observations.

Re: Why does current flow the opposite way from the electrons?

#175

Post by catlikesshrimp »

ArnoVW wrote: post #140
mrunkel wrote: post #94

Earlier quoted context omitted.

In German we use “Akku” which is short for “Akkumulator” for rechargeable batteries.

Or ‘pile’ in French, which is homonym for ‘stack’ because a battery is a stack of alternating materials.

Is that official? In spanish, decades ago, the word for battery was "Pila"

"Pila" is a heap of countable physical units, either stacked or disordered. But pila is commonly a fixture for liquids, like septic tank is pila séptica

And batteries were mostly lead-acid. Hence, a pile for/of acid.

Re: Why does current flow the opposite way from the electrons?

#176

Post by trelane »

joquarky wrote: post #169
bithive123 wrote: post #165

Earlier quoted context omitted.

Negation, being a concept, exists only in the mind. Same with "things". A thing is a noun; a part of speech. The "real world" is undifferentiated quanta.

Put simply, "the map is not the territory"

Or, as Monty Python has rightly pointed out, "it's only a model."

Re: Why does current flow the opposite way from the electrons?

#177

Post by juliushuijnk »

adrian_b wrote: post #171
lupire wrote: post #142

Earlier quoted context omitted.

Numbers do not exist in the world. Umbers exist outside the world.

I do not know if this is a joke about shadows that I did not get, or just a typo, but numbers exist in the world. The world is composed of things. The things are grouped in sets. Numbers are equivalence classes of sets. The set of the medium-sized planets of the Solar System is equivalent in number with the set of the big planets of the Solar System and also equivalent in number with the set of the big satellites of…

> The things are grouped in sets.

By who?

Re: Why does current flow the opposite way from the electrons?

#179

Post by znkr »

bithive123 wrote: post #165
adrian_b wrote: post #125

Earlier quoted context omitted.

The reason why which charge is named positive and which is named negative does not matter is because in all the equations that relate electric charge with other measurable physical quantities we never have an electric charge alone, but we always have the product of two electric charges. The value of the product of two electric charges is invariant to the convention chosen for the sign of the electric charge. Numbers…

Negation, being a concept, exists only in the mind. Same with "things". A thing is a noun; a part of speech. The "real world" is undifferentiated quanta.

Ceci n'est pas une pipe

Re: Why does current flow the opposite way from the electrons?

#180

Post by soloist11 »

vagab0nd wrote: post #139

The sign of the electron doesn't matter in this case. The definition of the direction of the current itself is also arbitrary. So are the definitions of positive and negative terminals. In fact, it is my understanding that most of the "left/right", "positive/negative", "north/south" definitions in EM are by convention. So the first guy calls it whatever they want and it doesn't matter at all.

The theory of charges has Z/2 symmetry.
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