Electricity (split from Science Project (static charge))

[westom]

14 hours ago, studiot said:

But westom is definitely wrong to say this:

So the electrical engineer who was doing this stuff for 50 years is wrong.   The electrical engineer who solved computer crashes created by static electric discharges is wrong. 

Electricity only exists when a positive and negative charge make a connection.  That negative charge cannot be created without creating a positive charge elsewhere.  So when we prevent static electric damage, earth ground appears nowhere in that solution.  Static electric prevention is always about making that connection from positive to negative charges via a path that is not destructive.

It is even a standard experiment in physics class.  Using Styrofoam balls to repel and attract.  Earth ground is also not found anywhere in that experiment.  What repells or attracts the charged ball?  Items charges positively or negatively.  A positive and negative charge always must exist to have any electricity - static or otherwise.  As even taught in high school physics.

Ground is only some other item no different than the styrofoam ball.  We simply call one item a ground only as a reference point for human conversation.  That styrofoam ball could just as easily be called ground.

As Strange notes, earth ground is just an extreme case of swansont's "discharging to a large conductive reservoir.  Or conductor.  That current (in a previous example) is still making a connection from charges in the hand to charges beneath feet - even if the resulting electric current completes that path via earth.

In another example, lightning is an electric current connecting charges in a cloud to charges in earth. Those earthborne charges are not everywhere in earth.  They are maybe four miles distant.  Shortest path is not five miles across the sky to those charges.  Shortest path is maybe three miles down (ie to a church steeple) and then four miles through earth to those distant charges.  Those charges are not everywhere in earth.  They remain in a region where they landed maybe five miles from the cloud.

Feynman, in his three volume book on physics, demonstrates this with a figure.

 

Edited December 18, 2019 by westom
spelling

[Strange]

4 minutes ago, westom said:

Electricity only exists when a positive and negative charge make a connection. 

You seem to be confusing “electricity” with “current”. Current requires a connection. Static electricity requires a separation of charges (no connection).

6 minutes ago, westom said:

What repells or attracts the charged ball?  Items charges positively or negatively. 

This is wrong. (Or so oversimplified it might as well be.)

[westom]

1 minute ago, Strange said:

You seem to be confusing “electricity” with “current”. Current requires a connection. Static electricity requires a separation of charges (no connection).

You apparently did not take course on Electromagnetic Theory or remember Maxwell's Equations.  Electricity only exists with movement - the moving of electrons.

Current is the amount of electrons moving.  Voltage is the potential energy (the E field) that makes that movement possible.  Apparently you have confused the E field with electricity.    Electricity only exists when both current and voltage exist.  And that means moving charges.

Static charges are just that.  Static.  No charge movement.  No electricity.  Electricity only exists when those charges are connected - moving electrons create a current.

Or from the E-M fields, static charges are a static field; not a time varying field.

Electricity only exists with a time varying field.  IOW both an E field and an H field must exist. Maxwell's equations.

Or from my E-M book, "Electric charges in motion constitute a current.  The unit of current is the ampere, defined as a rate of movement of charge passing a given reference point".  Which we might call ground.  "Current is thus defined as a motion of positive charges."

Static charges mean no charge movement - no current - no electricity.   Static charges and static electricity are two completely different items - discussed in that book, with equations, in two separate chapters.  Because they are different.

Apparently you have confused an Electric field with electricity.  Static electric discharge is the movement of charges.  That can only happen when a positive charge and a negative charge is connected by something electrically conductive.  Static charges means no charge movement.

Charges can exist in only one part of earth maybe four miles away.  Resulting in an electric current that travels through earth, for example, during a cloud to ground lightning strike.  Before the lightning strike, only static charges exist.  During the strike, static electricity exists.

 

[swansont]

10 hours ago, westom said:

You apparently did not take course on Electromagnetic Theory or remember Maxwell's Equations.  Electricity only exists with movement - the moving of electrons.
 

I did. I used "Introduction to Electrodynamics" by Griffiths as an undergrad. Funny how he thinks "electricity" covers static configurations as well, as he explains in the preface

"This is a textbook on electricity and magnetism, designed for an undergraduate course at the junior or senior level" (from the 4th edition)

He also cites several textbooks entitled "Electricity and Magnetism"

"Electricity" covers the whole of the subject — statics and dynamics.

 

Quote

Current is the amount of electrons moving. 

Actually it's not. It's the rate of charge moving — it depends on the amount of charge, and the speed of the charge. And it's not always electrons. (if you just know that a million electrons are moving, you do not know the current)

 

Quote

Voltage is the potential energy (the E field) that makes that movement possible. 

It's the potential energy per unit charge, and it's not the E field.

 

 

[westom]

11 hours ago, swansont said:

Actually it's not. It's the rate of charge moving — it depends on the amount of charge, and the speed of the charge. And it's not always electrons.

Correct.  But I was trying to keep is simpler.  Did not want to complicate issues with moving holes.

Point is that static charge is not electricity.  Electricity only exists when those 'charges' are moving.  Earth ground is unnecessary.  Only necessary to discharge is a connection from the positive and negative charges.  And both are probably somewhere in the building.

Lightning and protection of electronics from static discharges is all part of a same concept.  In every case, the discharge (an electric current) only exists when a conductor exists between those two charges.

[swansont]

2 hours ago, westom said:

Point is that static charge is not electricity.  Electricity only exists when those 'charges' are moving. 

No. Not supported by recognized experts of the subject. Or etymology.

“Since classical physics, it has been known that some materials, such as amber, attract lightweight particles after rubbing. The Greek word for amber, ήλεκτρον, or electron, was the source of the word 'electricity'”

https://en.m.wikipedia.org/wiki/Electrostatics

[Strange]

On 12/18/2019 at 3:23 AM, westom said:

Static electric protection

I thought there was no such thing as static electricity  

[studiot]

34 minutes ago, Strange said:

I thought there was no such thing as static electricity  

  +1

[westom]

2 hours ago, Strange said:

I thought there was no such thing as static electricity  

Static electricity is static charges that are not (yet) creating electricity.  As you also noted, the electricity (moving charges such as electrons) is created later.  Electricity only happens when charges are connected.

Earth ground remains irrelevant.

 

[Strange]

44 minutes ago, westom said:

Static electricity is static charges that are not (yet) creating electricity.  As you also noted, the electricity (moving charges such as electrons) is created later.  Electricity only happens when charges are connected.

I think you are going to face an uphill struggle trying to persuade everyone else in the world to accept your personal definition of the word "electricity".

Especially when even you can't avoid using it in the standard way: "Static electricity is static charges that are not (yet) creating electricity."

Quote

Earth ground remains irrelevant.

Nope. If you didn't connect your earthing strap to ground when handling sensitive component then you risk damaging them.

[westom]

1 hour ago, Strange said:

Nope. If you didn't connect your earthing strap to ground when handling sensitive component then you risk damaging them.

I don't expect to convince you of anything.  You are entrenched in a belief.  Charges that are not moving are somehow electricity.

Which ground? Logic ground is different from chassis ground which is different from floating ground which is different from ground beneath shoes (for static electricity) which is different from  receptacle safety ground which is different from AC utility substation ground which is different from water pipe ground which is different from motherboard ground which is different from analog ground which is different from ground plane for an antenna which is different from virtual ground which is different from automobile ground which is different from earth ground which is different from DC power ground or signal ground.

So connecting a wrist strap to motherboard ground will protect from static discharges?

Only connection that matters is one that connects charges in a body to charges beneath shoes.  Well, connecting to earth ground does eventually make that connection. But the only relevant ground is that where those charges exist.  For static electricity generated by a human, that is charges beneath shoes.

 

[Ghideon]

18 hours ago, westom said:

Point is that static charge is not electricity.

If static charge is not electricity, can you provide a definition of what a static charge is?

The following definition matches what how it was defined when i studied:
Electricity: a form of energy resulting from the existence of charged particles (such as electrons or protons), either statically as an accumulation of charge or dynamically as a current.
(Oxford English Dictionary)

[swansont]

2 hours ago, westom said:

I don't expect to convince you of anything.  You are entrenched in a belief.  Charges that are not moving are somehow electricity.

It’s based in how we study and teach physics. You might think otherwise, but non-mainstream science should be discussed in speculations. Open a thread there and explain how the physics of static charges doesn’t fall under “electricity” in the study of “Electricity and Magnetism”

[Strange]

6 hours ago, westom said:

I don't expect to convince you of anything.  You are entrenched in a belief. 

You will find most people have an "entrenched belief" in the standard meanings of words. You can make up your own definition, like saying that "glory" means "a nice knock-down argument" but don't expect anyone else to agree with you. But do expect people to tell you that your definition is wrong.

Quote

'But "glory" doesn't mean "a nice knock-down argument",' Alice objected.

'When I use a word,' Humpty Dumpty said, in rather a scornful tone, 'it means just what I choose it to mean — neither more nor less.'

'The question is,' said Alice, 'whether you can make words mean so many different things.'

'The question is,' said Humpty Dumpty, 'which is to be master — that's all.'

Through the Looking Glass, Lewis Carrol

[westom]

9 hours ago, Ghideon said:

If static charge is not electricity, can you provide a definition of what a static charge is?

The following definition matches what how it was defined when i studied:
Electricity: a form of energy resulting from the existence of charged particles (such as electrons or protons), either statically as an accumulation of charge or dynamically as a current.
 

Yes, electricity results if charges exist with different polarity. But that is only one requirement. No charges are moving (yet).  So no electricity exists (yet).

 

Electricity is defined by voltage and current. Both must exist.  Voltage is the potential energy between two charged points.  Current is the movement of charges (electrons).  That is from Maxwell's equations.

Build static charges by shuffling feet on (say) a carpet.  Now charges of opposite polarity exist in the body and beneath shoes.  No electricity exists yet.  Charges are only static.  Touch a computer case.  Now charges in the body connect to charges in the floor.  That movement is called electricity.  Electricity only exists during the discharge period.

Another requirement.  Both the E and H fields exist when electricity exists.  Static charges only create an E field; no H field.  So no electricity exists - yet.  Once those charges are moving, then an H field also exist - meaning electricity exists.

E-M Field courses discuss static charges.  And then other formulas apply when charges (electrons and holes) are moving when electricity exists.  Those are two separate topics.

Back to the OP's original post.  He though static charges must connect to earth.  Earth is irrelevant.  For example, a wrist strap only discharges the body when it connect to charges in the floor - beneath feet.  If it happens to use earth to complete a connection, then so be it.  But a better connection is from the wrist, through that wrist strap, directly to those charges in the floor.  Then the electric current is not anywhere in earth.

In his case, he need only identify where separate positive and negative charges are located.  A connect to an earth ground rod (as his teacher noted) is unnecessary.

 

[studiot]

On 12/17/2019 at 2:11 PM, FlamingoMan said:

On 12/17/2019 at 9:56 AM, studiot said:

You would need to describe the environment in more detail to figure out where to lead the collected charge to.

We were not told the environment.

 

Thinking further about this, you do need to know more about the circumstances.

 

On 12/16/2019 at 11:46 PM, FlamingoMan said:

We are doing a project on static electricity that is being built up from running on a treadmill. We have to build an invention using the idea of a lightning rod to get rid of the static charge (in other words kill the charge). We want to kill the charge because the person is getting shocked.

 

Do I understand that this is a theoretical exercise, not a practical one from these answers?

 

I ask because appropriate action depends upon where the person being shocked.

1) where the person acquires the charge

2) Where that person is being shocked by the discharge

 

As you pointed out it is very common for (some) people to aquire a charge through friction rubbing against clothing, carpets etc.

So I am assuming that this friction is when the person is running on the treadmill.

Subsequently the person either grabs a metal bar on the running machine and is shocked.
Or walks off, carrying the charge with him, and is subsequently shocked when he touches something metal, say the locker cabinet.

 

Earthing the bar on the running machine will not help with either of these situations, nor will sweeping up the opposite charge from the moving running platform.
Indeed the exposed metalwork may already be earthed.

In these circumstance the discharge has to take place somehow and so the action required is to limit the discharge current to a level where it is not noticeable.

Too slow the discharge down (thus limiting the current) you can interpose a partly conductive material (eg a wet towel) or if the discahrge is to a metal bar on the machine then wrap a permanent conductive foam layer round part of the bar for grabbing onto before touching the bare metal.

 

 

[Strange]

23 minutes ago, studiot said:

So I am assuming that this friction is when the person is running on the treadmill.

Subsequently the person either grabs a metal bar on the running machine and is shocked.
Or walks off, carrying the charge with him, and is subsequently shocked when he touches something metal, say the locker cabinet.

This was my interpretation as well. 

23 minutes ago, studiot said:

if the discahrge is to a metal bar on the machine then wrap a permanent conductive foam layer round part of the bar for grabbing onto before touching the bare metal

I think this is a good solution. It mustn't be too insulating, though or the static charge won't be discharged (or won't "turn into electricity" as some would have it).

If this is a purely theoretical scenario, then I think FlamingoMan has to describe all the assumptions they are making before going on to describe the proposed solution.

A tricky case is if the shock comes when the person on the treadmill touches the control panel to change the speed or stop the machine. (This may be worse psychologically, as well, because the user might think they are getting an electric shock from faulty equipment.) You can get flexible, transparent rubberised covers for equipment - normally intended to protect the equipment from water, but would work in this case to protect the user from static discharge.

(When I lived in Japan, during the winter I used to walk around the office holding a key so I could discharge myself against a doorknob before touching it. There would be a mighty spark, but because the current was distributed over an area of skin, you didn't feel it.  I can't see how this can be applied in this case, though.)

8 hours ago, westom said:

Electricity is defined by voltage and current. Both must exist.

Please provide a source for this definition. Or have you just made it up?

It is not one I am familiar with. And it is certainly not the only one (even ignoring metaphorical uses like "the atmosphere was electric").

Lets see what some of the usual reference sources for the meanings of words say... (spoiler alert: none of them agree with you)

Form the Encyclopaedia Brittanica:

Quote

Electricity, phenomenon associated with stationary or moving electric charges. 

https://www.britannica.com/science/electricity

From Collins Dictionary:

Quote

electricityin British English

(ɪlɛkˈtrɪsɪtɪ  , ˌiːlɛk-)

NOUN

1. 

any phenomenon associated with stationary or moving electrons, ions, or other charged particles

2. 

the science concerned with electricity

https://www.collinsdictionary.com/dictionary/english/electricity

From Wikipedia:

Quote

Static electricity is an imbalance of electric charges within or on the surface of a material. 

https://en.wikipedia.org/wiki/Static_electricity

8 hours ago, westom said:

For example, a wrist strap only discharges the body when it connect to charges in the floor

"Charges in the floor"? Are there monsters under your bed, too?

In the case of the OP, the opposite charges are presumably accumulated on the running belt not the floor.

[studiot]

9 hours ago, westom said:

Electricity is defined by voltage and current. Both must exist

It is possible to have voltage without current, and also current without voltage.

[Strange]

1 hour ago, studiot said:

It is possible to have voltage without current, and also current without voltage.

Ah, but apparently it isn’t “electricity” in that case (it is just “sparkling charge”).

[studiot]

8 minutes ago, Strange said:

Ah, but apparently it isn’t “electricity” in that case (it is just “sparkling charge”).

Apparently.

🤣

 

But I also said current without voltage, and current is a flow of charge.

So this particular sparkling charge is also flowing like the Champagne.

 

Cheers

[westom]

18 hours ago, studiot said:

It is possible to have voltage without current, and also current without voltage.

The word electricity has different meanings.   Another example demonstrates.  'Stress' on a human body increases health (it results in hormones that cause a body to repair itself).  Whereas 'stress' can cause premature illness and even contribute to death.  The word 'stress' describes two completely different and unrelated actions on a body.  And can be used subjectively to confuse and manipulate the naive.

Static charges were created by amber which was also called elektron.  Static charges created by amber were called electricity.  That was long before work by Orsted and others.  That word 'electricity' now describes two completely different phenomena in physics.   Elektron was long before Coulomb's law was a process of discovering and defining a different concept called electricity.

Electricity from elektron has no moving charges.  Only an E field created by those stationary charges was first called electricity.   No H field exists.  Once Faraday noted that moving charges create a H field, then Maxwell used and contributed to his work to create Maxwell's equations.  Those equation define the other thing that we all know as electricity: what happens only when electrons (charges) are moving.

Junk science will ignore all this.  Find a quote.  Take it out of context.  And then insist that 'static electricity'  and what we know only as 'electricity' are same.  Classic junk science reasoning.  Static electric has no moving charges.  It is not electricity.  It is 'static electricity'.  Which is completely different from 'electricity' also known as an electric current.  English nazis will have difficulty for the same reason they cannot understand the difference between 'stress' and 'stress'.

The British also fail to understand 'earth ground'.  Due to early misinformation, a safety ground (also called equipment ground) in a receptacle is called earth ground by the British.  Confusion created by a legacy.  Using that reasoning, the neutral wire should also be called a ground.  Why not?  Because 'earth ground' in a receptacle is completely different from 'earth ground' with an electrode stabbed into it.

But again, the naive will myopically focus on a dictionary definition without learning the always required underlying facts and numbers.  Then assume an 'earth ground' in a receptacle is same as an 'earth ground' that an electrode is buried in.  Misinformation and scams easily promoted using only word association.  Words are same.  That proves two completely different things must be same.  Bull.

There was a surge on Wall Street.  That means a tidal surge flooded that street?  The word 'surge', just like the word stress, just like the expressions 'earth ground',  and just like the word electricity; all have multiple meanings.  Misinformation is accurately exposed.

When two items are charged, only an E field exists.  We call that static charge "static electricity".  When those charges are connected; only for that short discharge time period do moving charges exist.  We call that discharge an "electric current".  "Static electricity" and an electric current ("electricity") are completely different.

  One has no moving charges, no H field, no current, and only a voltage measured in volts/meter.    Other has moving charges, must have an H field (as described by Maxwell's equations), has a current, and creates voltage measured in volts - a different unit of measure.  Notice how the dictionary describes both. It fails to note the same word describes two completely different phenomena.  Those first two sentences describe two completely different things - unfortunately both called electricity.

That difference is obvious when one learns from an E-M Fields course.

A voltage without current is the E field.  It is a static field - no H field exists.  When current exists, then an H field exists AND a voltage must exist to move those electrons (charges).

 

Edited December 21, 2019 by westom

[swansont]

6 hours ago, westom said:

Static charges were created by amber which was also called elektron.  Static charges created by amber were called electricity.  That was long before work by Orsted and others.  That word 'electricity' now describes two completely different phenomena in physics.   Elektron was long before Coulomb's law was a process of discovering and defining a different concept called electricity.

Electricity from elektron has no moving charges.  Only an E field created by those stationary charges was first called electricity.   No H field exists.  Once Faraday noted that moving charges create a H field, then Maxwell used and contributed to his work to create Maxwell's equations.  Those equation define the other thing that we all know as electricity: what happens only when electrons (charges) are moving.

Only when they are moving? Nope. Maxwell's equations work for static charges. The divergence of E is still proportional to the enclosed charge. The current only shows up in Ampere's law. 

 

6 hours ago, westom said:

Junk science will ignore all this.  Find a quote.  Take it out of context.  And then insist that 'static electricity'  and what we know only as 'electricity' are same. 

Using your example: Maxwell's equations describe both static and dynamic systems. It's not junk science. It's physics.

An extension of your thought process is that a bar magnet does not exhibit magnetism since there are no moving charges, which is clearly nonsense.

 

[studiot]

6 hours ago, westom said:

The word electricity has different meanings.   Another example demonstrates.  'Stress' on a human body increases health (it results in hormones that cause a body to repair itself).  Whereas 'stress' can cause premature illness and even contribute to death.  The word 'stress' describes two completely different and unrelated actions on a body.  And can be used subjectively to confuse and manipulate the naive.

Static charges were created by amber which was also called elektron.  Static charges created by amber were called electricity.  That was long before work by Orsted and others.  That word 'electricity' now describes two completely different phenomena in physics.   Elektron was long before Coulomb's law was a process of discovering and defining a different concept called electricity.

Electricity from elektron has no moving charges.  Only an E field created by those stationary charges was first called electricity.   No H field exists.  Once Faraday noted that moving charges create a H field, then Maxwell used and contributed to his work to create Maxwell's equations.  Those equation define the other thing that we all know as electricity: what happens only when electrons (charges) are moving.

Junk science will ignore all this.  Find a quote.  Take it out of context.  And then insist that 'static electricity'  and what we know only as 'electricity' are same.  Classic junk science reasoning.  Static electric has no moving charges.  It is not electricity.  It is 'static electricity'.  Which is completely different from 'electricity' also known as an electric current.  English nazis will have difficulty for the same reason they cannot understand the difference between 'stress' and 'stress'.

The British also fail to understand 'earth ground'.  Due to early misinformation, a safety ground (also called equipment ground) in a receptacle is called earth ground by the British.  Confusion created by a legacy.  Using that reasoning, the neutral wire should also be called a ground.  Why not?  Because 'earth ground' in a receptacle is completely different from 'earth ground' with an electrode stabbed into it.

But again, the naive will myopically focus on a dictionary definition without learning the always required underlying facts and numbers.  Then assume an 'earth ground' in a receptacle is same as an 'earth ground' that an electrode is buried in.  Misinformation and scams easily promoted using only word association.  Words are same.  That proves two completely different things must be same.  Bull.

There was a surge on Wall Street.  That means a tidal surge flooded that street?  The word 'surge', just like the word stress, just like the expressions 'earth ground',  and just like the word electricity; all have multiple meanings.  Misinformation is accurately exposed.

When two items are charged, only an E field exists.  We call that static charge "static electricity".  When those charges are connected; only for that short discharge time period do moving charges exist.  We call that discharge an "electric current".  "Static electricity" and an electric current ("electricity") are completely different.

  One has no moving charges, no H field, no current, and only a voltage measured in volts/meter.    Other has moving charges, must have an H field (as described by Maxwell's equations), has a current, and creates voltage measured in volts - a different unit of measure.  Notice how the dictionary describes both. It fails to note the same word describes two completely different phenomena.  Those first two sentences describe two completely different things - unfortunately both called electricity.

That difference is obvious when one learns from an E-M Fields course.

A voltage without current is the E field.  It is a static field - no H field exists.  When current exists, then an H field exists AND a voltage must exist to move those electrons (charges).

 

 

In an effort to preserve some clarity for the OP, I would observe that there is a difference between true, more exact or complete Physics theory and idealised theory we set up to apply th more exact to the everyday world.

In Mechanics we are much more up front about this and happily understand and employ light inextensible strings, frictionless motion etc.

But in electrical subjects we mix up the Physics with Circuit Theory, which is an artificial theory constructed using idealised circuit elements.
This is unfortunate as it leads many students to become confused.

So, westom, what pray is the voltage difference between any two points in a connecting wire carrying 1 kiloamp, 1 amp, 1 microamp?

In most Circuit theories (including Maxwell's) it is exactly zero.

 

Which brings me to my second point, and what seems to be one of your points of confusion.

'Voltage' is indeed a tad imprecise as it the unit for two different physical quantities.

Electrical potential and (electrical) potential difference.

Mixing these two up will doubtless lead to confusion.

 

Finally the terms 'earth' and 'ground' come from Circuit Theory, not from Maxwell and other fundamental Physics.

All the uses of either stem from the ability of this circuit element to sink or source any quantity of current without change in potential.

 

 

[Strange]

9 hours ago, westom said:

The word electricity has different meanings. 

Good. So you admit that your limited definition that "it must involve voltage and current" only applies to a subset of the uses of the word "electricity".

Now that we have got past that bit of nonsense, maybe we can move on.

9 hours ago, westom said:

The British also fail to understand 'earth ground'.  Due to early misinformation, a safety ground (also called equipment ground) in a receptacle is called earth ground by the British. 

No it isn't. It is just called "earth". (Although many people understand the American term "ground" as well. In fact the two might be equally commonly used now. But as I no longer do any engineering, I can't be sure.)

9 hours ago, westom said:

We call that discharge an "electric current".  "Static electricity" and an electric current ("electricity") are completely different.

They are certainly different. I don't think anyone would disagree. However, previously you said that one of them was not electricity, which is nonsensical.

[westom]

13 hours ago, Strange said:

They are certainly different. I don't think anyone would disagree. However, previously you said that one of them was not electricity, which is nonsensical.

"Static electricity" is not same as "electricity".  Those two words "static' and "electricity", when combined, clearly mean something different from the single word "electricity".  That is what I said much earlier and again recently.

To keep others from being confused, better is to replace the term "static electricity" with "static charges".

The "electricity" created by static charges is also called a "static electric discharge".  Those three words define something completely different from a two word term. "static electric".

 

 

16 hours ago, studiot said:

ISo, westom, what pray is the voltage difference between any two points in a connecting wire carrying 1 kiloamp, 1 amp, 1 microamp?

In most Circuit theories (including Maxwell's) it is exactly zero.

It is clearly not zero according to circuit theory.  Electricity is always different at both ends of a wire for so many reasons.  Including this.  All wire has impedance. So a voltage difference always exists with any current in a wire.  How big?  Not provided are many necessary parameters.  So no informed answer is possible.  Other than this.  A voltage difference always exists in two ends of every wire that is conducting a current.

When is voltage between both ends zero?  Only when no current flows.

 

OP's science project is always about where two separate charges reside. We simply locate the location of separate positive and negative charges.  Then call one of those locations ground.  That is the only relevant ground.  Either location can be called ground.