Why is the terminology in electrical engineering so redundant and confusing?

[Polaris-1]

True-Rock;

Flow of electricity is meant to perform certain Action/ Work, not merely number-of-electrons 'delivered' or accumulated! Action or Work like heating, cooling, rotating (fan), etc, can not be achieved by just, mere accumulation of something (electrons). They (whatever, electrons in the case of electricity) need to be delivered at a certain force (acceleration). Without a Force no useful (directed) Work is possible to accomplish!

Thus, Volt denotes electrons potential to 'move' at certain Force, i.e. acceleration. This becomes a Vector in mathematics. Whereas, quantity of electrons (Charge, Coulomb) is merely a Scalar quantity, i.e., cumulative (Sigma, Integration over time) quantity. If use water supply as an analogy, you must remember that is simply a cumulative, Scalar quantity, for which water meter is just a quantity integrator, nothing more.

Thus, measure of electricity delivered, is not just a Scalar or cumulative quantity like in case of water delivery, but how that electrical (Force, Vector quantity was delivered -- which is a function of varied appliances, such as lighting, fans, heating, etc., which is also further integrated over time to get an aggregate quantity as Energy (Force/Power delivered over time).

Work, Energy, Charge, etc -- Scalar quantities; cumulative over time

Force, Volt, Field, etc. -- Vector Quantity (involves acceleration); use vector math, X product of Volt X Ampere = Power;
Energy = Integral of (Power) over time

Velocity, Ampere, etc -- itself a Vector, but no Force is created as yet, Volt creates it.

 

[russ_watters]

I don't understand.. Are you saying Joules is not:

J = kg * m**2 / s**2

a ratio of mass and distance to time?

"A ratio of mass and distance to time" is Kg*m/s, not kg*m^2/s^2. You are ignoring the meaning of squaring things. Just like:

And also, I apologize... but why is ten squared dollars not dollars?

Ten squared dollars is a hundred dollars. So you would give me a hundred dollars and I'd give you ten dollars back. My point was that squaring something changes it. I'm not sure why you are ignoring that fact.

Anyway, again: since you at least recognize that Joules and Coulombs are incompatible (if not exactly understanding why), then do you agree that there is no easy way for an electric company to switch to charging for coulombs instead of kWh (which are just Joules times a conversion factor).

 

[True Rock]

True-Rock;

Flow of electricity is meant to perform certain Action/ Work, not merely number-of-electrons 'delivered' or accumulated! Action or Work like heating, cooling, rotating (fan), etc, can not be achieved by just, mere accumulation of something (electrons). They (whatever, electrons in the case of electricity) need to be delivered at a certain force (acceleration). Without a Force no useful (directed) Work is possible to accomplish!

Thus, Volt denotes electrons potential to 'move' at certain Force, i.e. acceleration. This becomes a Vector in mathematics. Whereas, quantity of electrons (Charge, Coulomb) is merely a Scalar quantity, i.e., cumulative (Sigma, Integration over time) quantity. If use water supply as an analogy, you must remember that is simply a cumulative, Scalar quantity, for which water meter is just a quantity integrator, nothing more.

Thus, measure of electricity delivered, is not just a Scalar or cumulative quantity like in case of water delivery, but how that electrical (Force, Vector quantity was delivered -- which is a function of varied appliances, such as lighting, fans, heating, etc., which is also further integrated over time to get an aggregate quantity as Energy (Force/Power delivered over time).

Work, Energy, Charge, etc -- Scalar quantities; cumulative over time

Force, Volt, Field, etc. -- Vector Quantity (involves acceleration); use vector math, X product of Volt X Ampere = Power;
Energy = Integral of (Power) over time

Velocity, Ampere, etc -- itself a Vector, but no Force is created as yet, Volt creates it.

Polaris-1, excellent! I have not read anything along the lines of your explanation. I've Googled "vector" with various electrical terminology and I think this is by far the most helpful explanation provided.

Your approach definitely provides me a way to do some research and gain a better understanding of the relationship between of Joules and Coulombs.

Thanks

 

[sophiecentaur]

Phinds, you make a valid point.
I think I see individuals are very adept at memorizing terminology and equations who really don't understand the science behind it... for the very unfortunate reason that all the memorization work doesn't leave time to actually understand the science.

I know there are many dedicated scientists spending time on trying to simplify and clarify scientific terminology.

I'll admit I may have a misunderstanding... but, I don't think so. I have reviewed dozens of sources of information and my immediate conclusion is:

1. Hardly anyone who tries to explain electricity measurements understands the nature of electricity.
2. This is a huge inhibitor to engaging highly intelligent people in science.

I have read your posts and I see a certain 'inverse snobbery' at work, regarding the strict academic approach to Electricity. If you have ever been actually involved in experiments and calculations, leading to getting something useful from Electricity, then you will realize that the rigour of the subject is not something we can do without. General arm waving will not build you a computer or a radio receiver, although it can sometimes give one a 'feeling' that you understand a bit about Electricity.
Someone who knows a lot about Electricity (and can deliver the goods) would never claim to "understand" it all. They would be far too humble. Also, they would have actually gone to the trouble of learning, in depth, all that stuff that you seem to find so tiresome.
The possession of 'high intelligence' does not necessarily imply a good potential for 'understanding' Science well. Many highly intelligent people choose to direct their intellect elsewhere but, given the right circumstances (like the Second World War or the desire to earn money, for instance) many bright people make the effort and learn enough to contribute to the field.
As with learning foreign languages and playing a musical instrument well, there is a vast amount of practice and rote learning involved. Pain before gain. You reject the pain at the expense of success with Electricity.

If you cannot see the point of learning what's necessary, you have clearly missed the point.

 

[russ_watters]

Also noteworthy here is that there are already units of energy that use electrons and coulombs: the electron-volt and the coulomb-volt. But you need the volts.

 

[NascentOxygen]

Why doesn't my residential electricity provider just bill me in coulombs (C) each month. Why do we have such ridiculous concoctions like kWh?

You have a good point, especially in light of the fact that your electricity supply voltage is held reasonably constant. But by billing you for kWH instead of coulombs it's saving you money, so that's probably a good enough reason. Right? Money talks!

You see, not every coulomb delivers you the same amount of energy, some coulombs might do only 65% of the work that others do. But if you were to tell the power authority that you are happy to pay full price for each coulomb, regardless, then if you are a big customer I'm sure they would fall over themselves in their haste to have you sign such for such a deal. By metering in kWH they are charging you for the actual energy delivered, meaning those coulombs working at less than full effort are automatically costed at a lower pro rata charge. Few customers take issue with that.

 

[sophiecentaur]

You have a good point, especially in light of the fact that your electricity supply voltage is held reasonably constant. But by billing you for kWH instead of coulombs it's saving you money, so that's probably a good enough reason. Right? Money talks!

You see, not every coulomb delivers you the same amount of energy, some coulombs might do only 65% of the work that others do. But if you were to tell the power authority that you are happy to pay full price for each coulomb, regardless, then if you are a big customer then I'm sure they would fall over themselves in their haste to have you sign such for such a deal. By metering in kWH they are charging you for the actual energy delivered, meaning those coulombs working at less than full effort are automatically costed at a lower pro rata charge.

The point is that you are buying Energy, because that's what heats your house and works your washing machine. Coulombs do not constitute Energy on their own, any more than the links on a bicycle chain provide motive power. TrueRock is trying to impose his own private version of Electrical Units in this and it just doesn't work. There is absolutely no direct correspondence between Coulombs and Joules. The Volts (Joules per Coulomb) must be stated.

 

[sophiecentaur]

. . . . . and, of course, with AC, there is no net transfer of Coulombs - so you don't actually get any!

 

[True Rock]

Well... after spending many hours reading various opinions on the topic... I am bemused to admit once again Wikipedia provided the explanation that provided the most help for my purpose. I am repeatedly astonished that this one source of information keeps popping up as the place I find answers to my questions.

Etymology of electricity

In physics the term quantity of electricity refers to the quantity of electric charge.
It is designated by the letter Q and in the SI system is measured in derived units called coulombs.

Charge, in the electrical sense, was first used in 1767.

The term quantity of electricity was once common in scientific publications.
It appears frequently in the writings of Franklin, Faraday, Maxwell, Millikan, and J. J. Thomson, and was even occasionally used by Einstein.
However, over the last hundred years the term "electricity" has been used by electric utility companies and the general public in a non-scientific way.

Today the vast majority of publications no longer refer to electricity as meaning electric charge.
Instead they speak of electricity as electromagnetic energy.
The definition has drifted even further, and many authors now use the word "electricity" to mean electric current (amperes), energy flow (watts), electrical potential (volts), or electric force.
Others refer to any electrical phenomena as kinds of electricity.

These multiple definitions are probably the reason that Quantity of Electricity has fallen into disfavor among scientists.
Physics textbooks no longer define Quantity of Electricity or Flow of Electricity.
Quantity of electricity is now regarded as an archaic usage, and it has slowly been replaced by the terms charge of electricity, then quantity of electric charge, and today simply charge.
Since the term electricity has increasingly become corrupted by contradictions and unscientific definitions, today's experts instead use the term charge to remove any possible confusion.

 

[russ_watters]

You have a good point, especially in light of the fact that your electricity supply voltage is held reasonably constant.

"Held constant", yes, but most customers use multiple voltages simultaneously. I use both 120 and 240V. Commercial services go as high as 13.2kV, three phase, so different users get vastly different amounts of energy for the same coulombs.

And I assume the rest of your post was about power factor. Another good reason why coulombs alone isn't enough.

 

[Drakkith]

Well... after spending many hours reading various opinions on the topic... I am bemused to admit once again Wikipedia provided the explanation that provided the most help for my purpose. I am repeatedly astonished that this one source of information keeps popping up as the place I find answers to my questions.

Etymology of electricity

In physics the term quantity of electricity refers to the quantity of electric charge.
It is designated by the letter Q and in the SI system is measured in derived units called coulombs.

Charge, in the electrical sense, was first used in 1767.

The term quantity of electricity was once common in scientific publications.
It appears frequently in the writings of Franklin, Faraday, Maxwell, Millikan, and J. J. Thomson, and was even occasionally used by Einstein.
However, over the last hundred years the term "electricity" has been used by electric utility companies and the general public in a non-scientific way.

Today the vast majority of publications no longer refer to electricity as meaning electric charge.
Instead they speak of electricity as electromagnetic energy.
The definition has drifted even further, and many authors now use the word "electricity" to mean electric current (amperes), energy flow (watts), electrical potential (volts), or electric force.
Others refer to any electrical phenomena as kinds of electricity.

These multiple definitions are probably the reason that Quantity of Electricity has fallen into disfavor among scientists.
Physics textbooks no longer define Quantity of Electricity or Flow of Electricity.
Quantity of electricity is now regarded as an archaic usage, and it has slowly been replaced by the terms charge of electricity, then quantity of electric charge, and today simply charge.
Since the term electricity has increasingly become corrupted by contradictions and unscientific definitions, today's experts instead use the term charge to remove any possible confusion.

Honestly I don't see what this has to do with the topic at hand. No one here, including yourself, ever talked about the term "electricity". All wikipedia is doing is saying that "electricity" is an ambiguous term nowadays. It still doesn't explain the relationship between all the terms you were asking about nor why they are defined as they are.

 

[M Quack]

Chapters 1 -- 18 of the famous Feynman lectures should provide you with a reasonable overview of "electricity" and a bit of the math that goes along with it. Coming from a Nobel prize winner you can probably trust his opinion on undergraduate material.

http://www.feynmanlectures.caltech.edu/II_toc.html

After that there is always Jackson's book, but that is not exactly bedside reading.

https://www.amazon.com/dp/047130932X/?tag=pfamazon01-20

 

[sophiecentaur]

In physics the term quantity of electricity refers to the quantity of electric charge.

Not on any regular basis. The term is not defined anywhere with serious authority that I know. Wiki may be ones friend when first approaching a topic but, as any Tom Dick or Harry can contribute to or modify it, it can never be taken as the ultimate arbiter of anything.
But why has it taken 40 Posts to get this far (i.e. nowhere)?

 

[davenn]

. . . . . and, of course, with AC, there is no net transfer of Coulombs - so you don't actually get any!

which is what I said many posts before yours ;)

The thread should have stayed locked ... its gotten nowhere as you stated :)
its sad that even after all this discussion, we still have a person who is completely unwilling to attempt to listen to and learn the basics :(

Dave

 

[Dale]

Re closed pending moderation

EDIT: the thread will remain closed this time.