To be Electricuted or not to be

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Insignificantinvisiblespo

Joined Nov 7, 2021
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Hi. To my understanding, the positive plate has no net charge and is only positive because its next to a plate that has a net negative charge.. So, to my understanding, the “positive” plate is really just a piece of metal with no net charge and is considered positive or negative relative to another plate. When we look at just the “positive” plate and ground, wouldn't that actually be looking at a regular piece of metel with no net charge and the actual earth which has no net charge and so the potential difference between the plate and earth should be zero, right? So if we placed our body between the positive plate and ground, we wouldn't get shocked, right?
 

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Insignificantinvisiblespo

Joined Nov 7, 2021
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Would a battery drain if you hooked up a wire from just the negative terminal to earth? Why or why not? Is that answer the same for the positive terminal to earth? Why or why not? Does your answer change if it was a 40,000 volt source? How come?
 

MrChips

Joined Oct 2, 2009
30,712
You are envisioning two situations:
(1) continuous charge flow
(2) instantaneous charge flow

(1) With a low voltage battery or similar power source you need a closed circuit in order for current to flow, for example, a light bulb connected across a battery.

(2) You need to consider capacitance effect, especially at very high voltages. In this case you get an instantaneous current flow in order to neutralize the electric field, think lightning bolts and electro-static discharge when you take off your sweater in winter months.

The charge on a capacitor is given by the formula:
Q = C x V

Whereas the energy stored goes up as the square of the voltage:
E = ½ x C x V x V

Hence you get a mightier zap as the voltage gets higher.
You don't need a completed circuit to be electrocuted.

 

Thread Starter

Insignificantinvisiblespo

Joined Nov 7, 2021
30
You are envisioning two situations:
(1) continuous charge flow
(2) instantaneous charge flow

(1) With a low voltage battery or similar power source you need a closed circuit in order for current to flow, for example, a light bulb connected across a battery.

(2) You need to consider capacitance effect, especially at very high voltages. In this case you get an instantaneous current flow in order to neutralize the electric field, think lightning bolts and electro-static discharge when you take off your sweater in winter months.
I read there is capacitance effect between high voltage AC transmission conductors. But my question is regarding only one conductor, as a plate, the positive plate, relative to ground, as my picture under my post illustrates. It is a dc situation, which i depicted with a plus and minus sign and why i didnt put a squiggly symbol for AC.
 

MrChips

Joined Oct 2, 2009
30,712
I don't know if that HV line is AC or DC.
DC is also used for very long EHV power transmission, sometimes at 1MV DC.

We are talking about charge flow. It doesn't matter if it is AC or DC.
 

nsaspook

Joined Aug 27, 2009
13,086
The people on the internet and the info on the internet is my teacher
A dangerous combination.

As has been said before 'electricity' is simply the phenomena of charge.
The phenomena was several types. Your question is more in the realm of:
The Static electricity phenomena (electrostatics) where have electrically isolated (charge separation) regions of charge and electric potentials (electric fields) between them.
https://www.britannica.com/science/electrostatics

Most common electronic circuits are in the realm of:
The Current electricity phenomena (electrodynamics) where we have potentials (from charge separation) that constantly move charge in a desired fashion.
 
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MrChips

Joined Oct 2, 2009
30,712
Hi. To my understanding, the positive plate has no net charge and is only positive because its next to a plate that has a net negative charge.. So, to my understanding, the “positive” plate is really just a piece of metal with no net charge and is considered positive or negative relative to another plate.
This is not correct.

An electric field is created between the two plates.
An excess of electrons on the negative plate induces a depletion of electrons on the positive plate.
When you connect your body between the positive plate and ground (or the negative plate alone and ground) there will be a redistribution of electrons through your body. Whether or not you get electrocuted depends on the circumstances and the energy transferred.

Don't try this out. You may never know the results.
 

Thread Starter

Insignificantinvisiblespo

Joined Nov 7, 2021
30
This is not correct.

An electric field is created between the two plates.
An excess of electrons on the negative plate induces a depletion of electrons on the positive plate.
When you connect your body between the positive plate and ground (or the negative plate alone and ground) there will be a redistribution of electrons through your body. Whether or not you get electrocuted depends on the circumstances and the energy transferred.

Don't try this out. You may never know the results.
Alright, but that makes many questions.
1: does that mean a battery will drain if just one of the terminals is connected to earth?
2: wouldnt that mean current would drain from the neutral wire to earth?
3: wouldnt that mean current leaks out of and gets sucked into both conductors and drains from the negative wire into the surrounding environment and sucks up electrons from the environment into the positive wire? Like, from the wire, along the electric field, to everything, including you and me right now?
4: does that mean the wires in my house are spraying out electrons, onto everything, and sucking them back off of everything back into the wires?
 
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MrChips

Joined Oct 2, 2009
30,712
No. As spook and I both said, you are confusing electrostatics and electrodynamics.
The battery will not drain because once the electrostatic forces are satisfied there is no electrodynamic current flowing.
 

Thread Starter

Insignificantinvisiblespo

Joined Nov 7, 2021
30
No. As spook and I both said, you are confusing electrostatics and electrodynamics.
The battery will not drain because once the electrostatic forces are satisfied there is no electrodynamic current flowing.
Thats interesting. I just looked into the difference between electrostatic and electrodynamic and one refers to moving charges while the other refers to charges not moving. Whats interesting is how can you differentiate the two with a no load situation?
 

nsaspook

Joined Aug 27, 2009
13,086
Thats interesting. I just looked into the difference between electrostatic and electrodynamic and one refers to moving charges while the other refers to charges not moving. Whats interesting is how can you differentiate the two with a no load situation?
What's more interesting is how did we get to the no-load situation as most real 'static' conditions are usually seen as quasi-static processes with a dynamic process (like a battery supplying potential energy) in equilibrium (no net flow of energy or matter). At any set instant in time and position in space they might seem the same but something happened before that point and something will happen afterward like the half-eaten cake.

1636824978570.png
 
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Thread Starter

Insignificantinvisiblespo

Joined Nov 7, 2021
30
What's more interesting is how did we get to the no-load situation as most real 'static' conditions are usually seen as quasi-static processes with a dynamic process (like a battery supplying potential energy) in equilibrium (no net flow of energy or matter). At any set instant in time and position in space they might seem the same but something happened before that point and something will happen afterward like the half-eaten cake.

View attachment 252614
Ok, but what i interpret from that is quasi-static ness should be ignored because overall a no load situation is net-static, if not, than all static situations should be considered dynamic.
 

nsaspook

Joined Aug 27, 2009
13,086
Ok, but what i interpret from that is quasi-static ness should be ignored because overall a no load situation is net-static, if not, than all static situations should be considered dynamic.
quasi-static ness give you a easier theoretical path from A to B in thermodynamics so you can track energy flows. For your electrical charged plate problem, a static situation indicator primarily means a lack of magnetic fields because of no moving charges. A body touching the circuit moves that into the dynamic realm as charges move to neutralize charge imbalances, generate magnetic fields in concert with electric fields to transfer energy. That will eventually become a static condition again if there is not a path for current electricity.

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