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| reqluq 2007-02-16, 5:25 pm |
| Ok, I was watching a doc on electricity, the bloke was explaining that dc
currect goes direct but ac currect goes to the load and back to the
generating plant. How is that? When does the load use it then if it goes
back to the plant?I thought that ac was a pulse type current.
Thanks for any clarification
req
| |
| Salmon Egg 2007-02-16, 5:25 pm |
| On 2/16/07 1:30 PM, in article 12tc8kad9uvq228@corp.supernews.com, "reqluq"
<scredcropshonnospam@hotmail.com> wrote:
> Ok, I was watching a doc on electricity, the bloke was explaining that dc
> currect goes direct but ac currect goes to the load and back to the
> generating plant. How is that? When does the load use it then if it goes
> back to the plant?I thought that ac was a pulse type current.
> Thanks for any clarification
> req
>
>
>
While I usually am skeptical of analogies, let me offer one. Consider
sawing. To cut through a piece of wood, you can use a band saw or circular
saw. You could also use a reciprocal saw such as the kind that has a handle
on both ends for which is used by two sawyers taking turns pulling the
blade. There are also saws that one person can use by pushing and pulling.
The band and circular saws go only in one direction. The other saws I
mention go in two directions. The former ones are dc, the latter ones are
ac.
Bill
-- Fermez le Bush--about two years to go.
| |
| Ben Miller 2007-02-16, 5:25 pm |
| "reqluq" <scredcropshonnospam@hotmail.com> wrote in message
news:12tc8kad9uvq228@corp.supernews.com...
> Ok, I was watching a doc on electricity, the bloke was explaining that dc
> currect goes direct but ac currect goes to the load and back to the
> generating plant. How is that? When does the load use it then if it goes
> back to the plant?I thought that ac was a pulse type current.
> Thanks for any clarification
> req
>
>
His explanation was really bad. Here is a simplified but more accurate one.
DC current flows in the same direction, at the same magnitude, constantly.
AC current varies it's magnitude and alternates direction, typically going
through a full cycle from (0 to +MAX to 0 to -MAX to 0) either 50 or 60
times a second depending on where you are located (speaking strictly about
power systems).
Electric current does does work (lights a light, produces heat, or rotates a
motor) regardless of which direction it flows, or whether it is direct or
alternating. Some of the equipment will be different for AC or DC
(particularly motors) and transformers only work with AC.
Ben Miller
--
Benjamin D. Miller, PE
B. MILLER ENGINEERING
www.bmillerengineering.com
| |
| Rheilly Phoull 2007-02-17, 3:25 am |
|
"reqluq" <scredcropshonnospam@hotmail.com> wrote in message
news:12tc8kad9uvq228@corp.supernews.com...
> Ok, I was watching a doc on electricity, the bloke was explaining that dc
> currect goes direct but ac currect goes to the load and back to the
> generating plant. How is that? When does the load use it then if it goes
> back to the plant?I thought that ac was a pulse type current.
> Thanks for any clarification
> req
>
>
Probably better to think of it as others have said, the current lows
backwards and forwards through the load doing work in either direction.
--
Cheers .......... Rheilly P
| |
| Tick Tock 2007-02-17, 3:25 am |
| Hey when you explain these things you have to forget using Lysergic Acid
Analogy;-) non technical or enigineering savy persona can understand
these concepts well as they are.
The bests is Phouls ( shame shame 
The Generator Pulls and Gives Energy with every Oscilation at the rates
Ben mentioned. (electromagnetic ~ mechanical turn)...
So' now I trust you can see how it sends a pulse, that expells and
retrieves Electrical Energy from the System.
You see Water going down the drain apparently lost forever too, but it
is collected in the Sewer & Drain system - the same is achieved in those
Electrical Power AC System, and the Utility Collects it in Billings for
now........ (teeheehee)
~ Tick Tock ~
| |
| contrex 2007-02-17, 3:25 am |
| On 16 Feb, 21:30, "reqluq" <scredcropshonnos...@hotmail.com> wrote:
> Ok, I was watching a doc on electricity, the bloke was explaining that dc
> currect goes direct but ac currect goes to the load and back to the
> generating plant. How is that? When does the load use it then if it goes
> back to the plant?I thought that ac was a pulse type current.
> Thanks for any clarification
> req
This reminds me of the beginner who, having absorbed the notion that a
flow of electric current requires a complete circuit, asked "Why does
the electricty company bill me when they get the electricity back
again?".
| |
| Salmon Egg 2007-02-17, 5:25 pm |
| On 2/17/07 12:45 AM, in article
1171701906.831947.224410@v33g2000cwv.googlegroups.com, "contrex"
<mike.j.harvey@gmail.com> wrote:
> On 16 Feb, 21:30, "reqluq" <scredcropshonnos...@hotmail.com> wrote:
>
> This reminds me of the beginner who, having absorbed the notion that a
> flow of electric current requires a complete circuit, asked "Why does
> the electricty company bill me when they get the electricity back
> again?".
>
The same is true for water, at least in Los Angeles. You pay for the water
and then pay for the sewerage. If you can prove that you do not send the
water back, the sewerage charge will be reduced.
Bill
-- Fermez le Bush--about two years to go.
| |
| reqluq 2007-02-17, 5:25 pm |
|
"Salmon Egg" <salmonegg@sbcglobal.net> wrote in message
news:C1FB6B98.62B77%salmonegg@sbcglobal.net...
> On 2/16/07 1:30 PM, in article 12tc8kad9uvq228@corp.supernews.com,
> "reqluq"
> <scredcropshonnospam@hotmail.com> wrote:
>
> While I usually am skeptical of analogies, let me offer one.
I suggest in future you stay skeptical and don't try the analogy thing :-)
>Consider
> sawing. To cut through a piece of wood, you can use a band saw or circular
> saw. You could also use a reciprocal saw such as the kind that has a
> handle
> on both ends for which is used by two sawyers taking turns pulling the
> blade. There are also saws that one person can use by pushing and pulling.
>
> The band and circular saws go only in one direction. The other saws I
> mention go in two directions. The former ones are dc, the latter ones are
> ac.
>
> Bill
> -- Fermez le Bush--about two years to go.
>
>
>
| |
| reqluq 2007-02-17, 5:25 pm |
|
"Ben Miller" <benmiller@worldnet.att.net> wrote in message
news:iIednavMVPvzrkvYnZ2dnUVZ_segnZ2d@comcast.com...
> "reqluq" <scredcropshonnospam@hotmail.com> wrote in message
> news:12tc8kad9uvq228@corp.supernews.com...
>
> His explanation was really bad.
Agreed
>Here is a simplified
Not agreed
>but more accurate one.
I'm not qualified to give a response to whether it's accurate or not.
> DC current flows in the same direction, at the same magnitude, constantly.
> AC current varies it's magnitude and alternates direction, typically going
> through a full cycle from (0 to +MAX to 0 to -MAX to 0) either 50 or 60
> times a second depending on where you are located (speaking strictly about
> power systems).
>
> Electric current does does work (lights a light, produces heat, or rotates
> a motor) regardless of which direction it flows, or whether it is direct
> or alternating. Some of the equipment will be different for AC or DC
> (particularly motors) and transformers only work with AC.
>
> Ben Miller
I want to hear: Yes or No; it does/does not go back to the plant, and this
is how it does it.
I want to know if I lived one light year, or say, an infinity away, and I
turned on the light and it took too long to get back to the plant because of
the vast distance from the load (if it really goes to the load and back)
would that then be in essence DC currect because it's to far to make the
cycle back?
req
| |
| reqluq 2007-02-17, 5:25 pm |
|
"Rheilly Phoull" <rheilly@bigpong.com.au> wrote in message
news:45d682a1$0$24733$5a62ac22@per-qv1-newsreader-01.iinet.net.au...
>
> "reqluq" <scredcropshonnospam@hotmail.com> wrote in message
> news:12tc8kad9uvq228@corp.supernews.com...
> Probably better to think of it as others have said, the current lows
> backwards and forwards through the load doing work in either direction.
> --
> Cheers .......... Rheilly P
All of the current? you mean none gets used? So on the way back to the plant
( after passing back through the meter) theoretically I could tap into it
and get some free currenct?
req
| |
| reqluq 2007-02-17, 5:25 pm |
| "Tick Tock" <Fromthebeginning@webtv.net> wrote in message
news:22229-45D6BC67-479@storefull-3251.bay.webtv.net...
> Hey when you explain these things you have to forget using Lysergic Acid
What the hell is lysergic acid? :-)
> Analogy;-) non technical or enigineering savy persona can understand
> these concepts well as they are.
>
> The bests is Phouls ( shame shame
>
> The Generator Pulls and Gives Energy with every Oscilation at the rates
Here we go again... where does it *pull* energy from?
> Ben mentioned. (electromagnetic ~ mechanical turn)...
>
> So' now I trust you can see how it sends a pulse, that expells and
> retrieves Electrical Energy from the System.
>
> You see Water going down the drain apparently lost forever too, but it
> is collected in the Sewer & Drain system - the same is achieved in those
> Electrical Power AC System, and the Utility Collects it in Billings for
> now........ (teeheehee)
>
> ~ Tick Tock ~
>
>
| |
| reqluq 2007-02-17, 5:25 pm |
| "contrex" <mike.j.harvey@gmail.com> wrote in message
news:1171701906.831947.224410@v33g2000cwv.googlegroups.com...
> On 16 Feb, 21:30, "reqluq" <scredcropshonnos...@hotmail.com> wrote:
>
> This reminds me of the beginner who, having absorbed the notion that a
> flow of electric current requires a complete circuit, asked "Why does
> the electricty company bill me when they get the electricity back
> again?".
Do they really get it back? are you saying it there is no loss when I use my
dryer?
req
| |
| Long Ranger 2007-02-17, 8:25 pm |
|
"reqluq" <scredcropshonnospam@hotmail.com> wrote in message
news:12teqkpivmhjhf8@corp.supernews.com...
>
> "Rheilly Phoull" <rheilly@bigpong.com.au> wrote in message
> news:45d682a1$0$24733$5a62ac22@per-qv1-newsreader-01.iinet.net.au...
> All of the current? you mean none gets used? So on the way back to the
> plant ( after passing back through the meter) theoretically I could tap
> into it and get some free currenct?
> req
> Think of a hydraulic pump and motor here. The pump moves the fluid through
> a tube and it goes through the motor and makes it turn. Barring any leaks,
> every gallon of fluid that goes out, comes back to the storage tank and is
> recirculated. Same with electric current. When an electron moves into one
> side of the circuit, one moves out of the other side. An AC electric motor
> is configured to take advantage of a current that changes state so it
> converts it to a rotational force. Now think about two piston pumps on
> each end of that hydraulic system. One pushing out and discharging into
> the system, while the other sucks in and receives fluid. Then they
> alternate and the other pushes, and the opposite sucks, so that the fluid
> is moving back and forth. Now envision the end of a shaft you need to
> rotate, and when the fluid goes one way, it flows across vanes on the top
> of the shaft, and when it goes the other, check valving makes it flow
> across the bottom vanes in an opposite direction, thereby creating the
> same direction of rotation from two different directions of flow. That is
> not an exact analogy for how a motor digests AC, but it will get you on
> the path of "where the current goes". It just recirculates, and it causes
> changes in the things it circulates through. It doesn't burn up and go
> anywhere else. It is just pushing electrons around like a pump might push
> fluid in a closed system.
| |
| Anthony 2007-02-18, 3:25 am |
| "reqluq" <scredcropshonnospam@hotmail.com> wrote in
news:12teqoqk4cs7i5d@corp.supernews.com:
> Do they really get it back? are you saying it there is no loss when I
> use my dryer?
> req
Yes, there is loss, because the dryer converts the electrical energy into
heat energy.
--
Anthony
You can't 'idiot proof' anything....every time you try, they just make
better idiots.
Remove sp to reply via email
| |
| Don Kelly 2007-02-18, 3:25 am |
| "reqluq" <scredcropshonnospam@hotmail.com> wrote in message
news:12teqkpivmhjhf8@corp.supernews.com...
>
> "Rheilly Phoull" <rheilly@bigpong.com.au> wrote in message
> news:45d682a1$0$24733$5a62ac22@per-qv1-newsreader-01.iinet.net.au...
> All of the current? you mean none gets used? So on the way back to the
> plant ( after passing back through the meter) theoretically I could tap
> into it and get some free currenct?
> req
----------------------
All the current. Note that current is not power or energy. You can measure
the same current in the return that you have going to the load.
One of the basic laws is Kirchoff's current law which can be described as
"what goes in comes out". This is true at any cross-section of the circuit
so one can have a source-line-load-return line loop where the current is the
same everywhere.
When you think of supplying a load, you have to consider both voltage and
current (which produce power. For example, you could have a 13 volt battery
supplying a load resistance of 6 ohms. The wires and battery may have
resistance of 0.5 ohms so the total resistance is 6.5 ohms. The current will
be 13/6.5 =2A everywhere in the circuit. The voltage across the 6 ohm load
will be 6*2 =12V and the voltage drop in the wires,etc will be 0.5*2 =1V.
Total 13V. The load power is 12*2 =24 Watts and the source will supply 13*2
=26 watts. The difference is the power loss in the wires (I^2R =4*0.5
=2Watts).
Sure you can tap into the wire and add another load- say another 6.5 ohms
but the result is that now the current will be 1A and the various powers and
voltages will change accordingly. Try two 3V flashlight bulbs in series
supplied by two D cells in series (as in a normal flashlight), you will
have two very dim lights.
This is true for DC and also for AC (a bit more complicated ). For AC the
polarity of the voltage supplied changes every cycle so the current also
reverses accordingly. Don't try to mentally follow electrons flowing as for
AC they simply wobble around while the energy "flows" at near light speed.
Even for DC, the electrons (or other charge carriers) simply drift along
lazily and the speed or location of an individual electron is neither of
concern nor measurable. --
Don Kelly dhky@shawcross.ca
remove the X to answer
----------------------------
| |
| Rheilly Phoull 2007-02-18, 3:25 am |
|
"Anthony" <tonytn36sp@hotmail.com> wrote in message
news:Xns98DAE5CC1C7Dacziparle3sp835@216.77.188.18...
> "reqluq" <scredcropshonnospam@hotmail.com> wrote in
> news:12teqoqk4cs7i5d@corp.supernews.com:
>
>
>
> Yes, there is loss, because the dryer converts the electrical energy into
> heat energy.
>
>
> --
> Anthony
>
> You can't 'idiot proof' anything....every time you try, they just make
> better idiots.
>
> Remove sp to reply via email
Sure the energy is flowing in and out of the power station but it takes
applied energy to make it do that. I.e a gas turbine or diesel prime mover
etc. thats why there are charges made for you providing a resistance to that
flow with your load. Naturally there are losses in transmission and you of
course pay for any inefficiencies in your equipment.
--
Cheers .......... Rheilly P.
| |
| TimPerry 2007-02-18, 3:25 am |
| reqluq wrote:[color=darkred]
> "Salmon Egg" <salmonegg@sbcglobal.net> wrote in message
> news:C1FB6B98.62B77%salmonegg@sbcglobal.net...
>
> I suggest in future you stay skeptical and don't try the analogy
> thing :-)
>
sometimes the old saws are the best.
i guess if we mixed this with the water analogy we would get rust.
| |
| Ben Miller 2007-02-18, 1:25 pm |
| "reqluq" <scredcropshonnospam@hotmail.com> wrote in message
news:12teqkp6ljd3uf7@corp.supernews.com...
>
> I want to hear: Yes or No; it does/does not go back to the plant, and
> this is how it does it.
Current flows in a complete circuit, so regardless of which direction it is
flowing, it leaves the generator in one or more lines, and returns in
others. So yes, the current goes out and back. However, the current that
returns is at a low potential, and can not do any more work. The generator
must lift that current to a higher potential before it can go out again.
Current is NOT power. If the current does any work or produces any heat out
on the circuit, then that is power that the generator produces, which does
not return. It is gone, and your electric meter accumulates it over time
(energy), and you pay for it.
Ben Miller
--
Benjamin D. Miller, PE
B. MILLER ENGINEERING
www.bmillerengineering.com
| |
|
| reqluq wrote:
>
>
> Here we go again... where does it *pull* energy from?
It is really all about extracting energy from
somewhere and delivering it in a usable form
somewhere else.
Don't get lost in the terms used (easy to do).
Take a gasoline engine and hook it to a generator.
The gasoline burns, which converts chemical energy
to heat energy. The heat energy causes gas to
expand - that motion has kinetic energy. That motion
spins the generator, and the kinetic energy is
converted to electrical energy. Thus someone could
say the generator "pulls" energy from the rotation of
the engine crankshaft, which in turn "pulls" energy
from the expanding gas, which in turn "pulls" energy
from the heat produced by the combustion of the
gasoline, which in turn had the energy stored in it
chemically.
Ed
| |
| AL BENSER 2007-02-19, 8:25 pm |
| In both AC and DC current, there is nothing that goes from the generator
to the load and back to the generator !!!! The electric current consists of
"motion of electrons". . . . The voltage created in a generator wants to
"push" electrons out. . . . and any one electron (in the conductor) goes
only from one atom to the next atom, and that motion has the speed of
light!!!!. Once an atom receive an extra electron, that atom will force one
of its own electron to travel to the next atom, and so on. . . . like if you
have a along train stopped on its track and you give a jolt to the first
wagon,
you find that the last wagon will jump.
"reqluq" <scredcropshonnospam@hotmail.com> wrote in message
news:12tc8kad9uvq228@corp.supernews.com...
> Ok, I was watching a doc on electricity, the bloke was explaining that dc
> currect goes direct but ac currect goes to the load and back to the
> generating plant. How is that? When does the load use it then if it goes
> back to the plant?I thought that ac was a pulse type current.
> Thanks for any clarification
> req
>
>
| |
| Tick Tock 2007-02-19, 8:25 pm |
|
reqluq
"Tick Tock" wrote in message
Hey when you explain these things you have to forget using Lysergic Acid
What the hell is lysergic acid? :-)
DoN't ask' that must be how that all must have started :-D
Analogy;-) non technical or enigineering savy persona can understand
these concepts well as they are.
The bests is Phouls ( shamen shame
The Generator Pulls and Gives Energy with every Oscilation at the rates
Here we go again... where does it *pull* energy from?
From HERE: when the north & south poles of the magnetic metal in the
rotor spin around the non-magnetic electrified metals in the stator....
& proportionally reverse for the windings & metals of The Generator
Ben mentioned. (electromagnetic (Metals with Magnetic Properties PULL )~
mechanical turns (or windings)...!!
>DoN't be a numbskull>
So' now I trust you can see how it sends a pulse, that expells and
retrieves Electrical Energy from the System.
You see Water going down the drain apparently lost forever too, but it
is collected in the Sewer & Drain system - the same is achieved in those
Electrical Power AC System, and the Utility Collects it in Billings for
now........ (teepeemee)
~ Tick Tock ~
| |
| John E. 2007-02-20, 3:25 am |
| AL BENSER sez:
> In both AC and DC current, there is nothing that goes from the generator
> to the load and back to the generator !!!! The electric current consists of
> "motion of electrons". . . . The voltage created in a generator wants to
> "push" electrons out. . . . and any one electron (in the conductor) goes
> only from one atom to the next atom, and that motion has the speed of
> light!!!!. Once an atom receive an extra electron, that atom will force one
> of its own electron to travel to the next atom, and so on. . . . like if you
> have a along train stopped on its track and you give a jolt to the first
> wagon, you find that the last wagon will jump.
Possibly one more analogy:
2 pulleys, one at the power station, one at your home, and a rope is run
around both, making a complete circuit. At your home, a fan is attached to
the pulley. For purposes of this example, let's say it's not a rotary fan,
but one of those found in stereotypes of mid-eastern 30's films, the kind
that wave back and forth.
When someone at the power station pulls on the rope so that it moves one
direction around the pulleys, the fan moves. Your home gets cooled. This is
similar to the way DC works
When they pull on the rope such that it goes back and forth only a few
inches, the fan still goes back and forth. Your home gets cooled. This is
similar to the way AC works
In both cases, work is accomplished, and in neither case does the rope "go
back to the power station".
Hope this helps...
--
John English
| |
| Ben Miller 2007-02-20, 9:25 am |
| "John E." <incognito@yahoo.com> wrote in message
news:0001HW.C1FFE3F0022E3B9CF04076C8@news.readfreenews.net...
> AL BENSER sez:
>
The same electron doesn't actually return to the genertor, but electric
current does. You can measure its magnitude and direction on both lines. At
any point along the circuit, current in must equal current out, and you can
follow that all the way around from the supply terminal to the return
terminal of the generator. If current doesn't flow back into the generator,
then cut one power line and everything should still work!
[color=darkred]
>
> Possibly one more analogy:
> 2 pulleys, one at the power station, one at your home, and a rope is run
> around both, making a complete circuit. At your home, a fan is attached to
> the pulley. For purposes of this example, let's say it's not a rotary fan,
> but one of those found in stereotypes of mid-eastern 30's films, the kind
> that wave back and forth.
>
> When someone at the power station pulls on the rope so that it moves one
> direction around the pulleys, the fan moves. Your home gets cooled. This
> is
> similar to the way DC works
>
> When they pull on the rope such that it goes back and forth only a few
> inches, the fan still goes back and forth. Your home gets cooled. This is
> similar to the way AC works
>
> In both cases, work is accomplished, and in neither case does the rope "go
> back to the power station".
>
> Hope this helps...
> --
> John English
>
So if you push 10 inches of rope out, 10 inches of rope doesn't enter the
other side? Cut the rope and see what happens. Suppose you have twenty feet
of rope at the far end, not looped, and you pull it all in past the fan,
don't you end up with a twenty foot coil of rope on the floor and no more
ability to power the fan unless you walk back out with the rope and then
pull it through again? So the rope must make a complete circuit for
continuous power transfer.
In both cases, the thing that doesn't return is the power. Either the
electrical power from the generator, or your mechanical effort moving the
rope, are what provide power to the load. You eat food or the generator
prime mover gets fuel in order to produce that power.
Ben Miller
--
Benjamin D. Miller, PE
B. MILLER ENGINEERING
www.bmillerengineering.com
| |
| AL BENSER 2007-02-20, 1:25 pm |
|
"Ben Miller" <benmiller@worldnet.att.net> wrote in message
news:B8GdnfhAdqKQn0bYnZ2dnUVZ_rylnZ2d@comcast.com...
> "John E." <incognito@yahoo.com> wrote in message
> news:0001HW.C1FFE3F0022E3B9CF04076C8@news.readfreenews.net...
>
> The same electron doesn't actually return to the genertor, but electric
> current does. You can measure its magnitude and direction on both lines.
> At any point along the circuit, current in must equal current out, and you
> can follow that all the way around from the supply terminal to the return
> terminal of the generator. If current doesn't flow back into the
> generator, then cut one power line and everything should still work!
>
ones that come back to it!! Then, what to you mean by 'the electric current
does' go back'??. What IS electric current??? the "ampere", which is the
unit
to measure electric current, is simply "so many electrons flow per second".
By the way, Mr Ampere was a Frenchman.
[color=darkred]
>
> So if you push 10 inches of rope out, 10 inches of rope doesn't enter the
> other side? Cut the rope and see what happens. Suppose you have twenty
> feet of rope at the far end, not looped, and you pull it all in past the
> fan, don't you end up with a twenty foot coil of rope on the floor and no
> more ability to power the fan unless you walk back out with the rope and
> then pull it through again? So the rope must make a complete circuit for
> continuous power transfer.
>
> In both cases, the thing that doesn't return is the power. Either the
> electrical power from the generator, or your mechanical effort moving the
> rope, are what provide power to the load. You eat food or the generator
> prime mover gets fuel in order to produce that power.
>
> Ben Miller
>
> --
> Benjamin D. Miller, PE
> B. MILLER ENGINEERING
> www.bmillerengineering.com
>
| |
| Salmon Egg 2007-02-20, 5:25 pm |
| On 2/20/07 6:13 AM, in article B8GdnfhAdqKQn0bYnZ2dnUVZ_rylnZ2d@comcast.com,
"Ben Miller" <benmiller@worldnet.att.net> wrote:
> The same electron doesn't actually return to the genertor, but electric
> current does. You can measure its magnitude and direction on both lines. At
> any point along the circuit, current in must equal current out, and you can
> follow that all the way around from the supply terminal to the return
> terminal of the generator. If current doesn't flow back into the generator,
> then cut one power line and everything should still work!
Electrons are indistinguishable from one another. Thus, you cannot
authoritatively say that that. In quantum mechanics, it is this
indistinguishability that leads to Fermi-Dirac statistics fundamental to a
simple electron theory of metals and photoemission.
Bill
-- Fermez le Bush--about two years to go.
| |
| Ben Miller 2007-02-20, 5:25 pm |
| "Salmon Egg" <salmonegg@sbcglobal.net> wrote in message
news:C2008ED7.63D8D%salmonegg@sbcglobal.net...
> On 2/20/07 6:13 AM, in article
> B8GdnfhAdqKQn0bYnZ2dnUVZ_rylnZ2d@comcast.com,
> "Ben Miller" <benmiller@worldnet.att.net> wrote:
>
>
> Electrons are indistinguishable from one another. Thus, you cannot
> authoritatively say that that. In quantum mechanics, it is this
> indistinguishability that leads to Fermi-Dirac statistics fundamental to a
> simple electron theory of metals and photoemission.
>
> Bill
> -- Fermez le Bush--about two years to go.
>
>
Excellent point. I should have said "The same electron doesn't necessarily
return to the generator...", leaving open the possibility.
Ben MIller
--
Benjamin D. Miller, PE
B. MILLER ENGINEERING
www.bmillerengineering.com
| |
| Don Kelly 2007-02-21, 3:25 am |
| "Ben Miller" <benmiller@worldnet.att.net> wrote in message
news:C6ydncYohbVIxkbYnZ2dnUVZ_ternZ2d@comcast.com...
> "Salmon Egg" <salmonegg@sbcglobal.net> wrote in message
> news:C2008ED7.63D8D%salmonegg@sbcglobal.net...
>
> Excellent point. I should have said "The same electron doesn't necessarily
> return to the generator...", leaving open the possibility.
>
> Ben MIller
> --
> Benjamin D. Miller, PE
> B. MILLER ENGINEERING
> www.bmillerengineering.com
In fact, it is unlikely that an individual electron will make the circle
tour with AC as the "drift" velocity is low so that the electrons typically
wobble around a bit. At least that is what appears to be the case -as Bill
says, we cannot distinguish individual charge carriers- so why bother in
cases where there are so damn many of them that statistical behaviour
becomes indistinguishable from the deterministic behaviour upon which our
circuit models are based?
Rather than consider electrons be gross and consider energy flow which is
what really matters.
--
Don Kelly dhky@shawcross.ca
remove the X to answer
----------------------------
| |
| AL BENSER 2007-02-21, 1:25 pm |
| I am quite surprise about all the philosophying on this issue!!
Any electrons leaving the generator at the power plant CAN NOT
reach any load because the generator output feeds only a step-up
transformer, providing physical isolation.
Yes, the current "out" of the generator is and must equal to the current
"in". But, the electrons making up that current can come from any source,
copper, aluminum or any conductor.
Yes, the electrons are indistinguishable from one another. Quantum
mechanics is irrelevant here.
"Don Kelly" <dhky@shaw.ca> wrote in message
news:JsPCh.1066521$1T2.709471@pd7urf2no...
> "Ben Miller" <benmiller@worldnet.att.net> wrote in message
> news:C6ydncYohbVIxkbYnZ2dnUVZ_ternZ2d@comcast.com...
>
>
> In fact, it is unlikely that an individual electron will make the circle
> tour with AC as the "drift" velocity is low so that the electrons
> typically wobble around a bit. At least that is what appears to be the
> case -as Bill says, we cannot distinguish individual charge carriers- so
> why bother in cases where there are so damn many of them that statistical
> behaviour becomes indistinguishable from the deterministic behaviour upon
> which our circuit models are based?
> Rather than consider electrons be gross and consider energy flow which is
> what really matters.
>
> --
>
> Don Kelly dhky@shawcross.ca
> remove the X to answer
> ----------------------------
>
>
| |
| phil-news-nospam@ipal.net 2007-02-21, 5:25 pm |
| On Wed, 21 Feb 2007 03:59:37 GMT Don Kelly <dhky@shaw.ca> wrote:
| In fact, it is unlikely that an individual electron will make the circle
| tour with AC as the "drift" velocity is low so that the electrons typically
| wobble around a bit. At least that is what appears to be the case -as Bill
| says, we cannot distinguish individual charge carriers- so why bother in
| cases where there are so damn many of them that statistical behaviour
| becomes indistinguishable from the deterministic behaviour upon which our
| circuit models are based?
Is the drift rate equally low in an arc?
--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
| first name lower case at ipal.net / spamtrap-2007-02-21-1645@ipal.net |
|------------------------------------/-------------------------------------|
| |
| Don Kelly 2007-02-22, 3:25 am |
| <phil-news-nospam@ipal.net> wrote in message
news:erii473bou@news1.newsguy.com...
> On Wed, 21 Feb 2007 03:59:37 GMT Don Kelly <dhky@shaw.ca> wrote:
>
> | In fact, it is unlikely that an individual electron will make the circle
> | tour with AC as the "drift" velocity is low so that the electrons
> typically
> | wobble around a bit. At least that is what appears to be the case -as
> Bill
> | says, we cannot distinguish individual charge carriers- so why bother in
> | cases where there are so damn many of them that statistical behaviour
> | becomes indistinguishable from the deterministic behaviour upon which
> our
> | circuit models are based?
>
> Is the drift rate equally low in an arc?
---------
Nope: but an arc involves ionization, both positive ions and electrons,
etc - whole new ball game. Note that the current in an arc is generally
limited by the rest of the circuit, not the arc.
--
Don Kelly dhky@shawcross.ca
remove the X to answer
----------------------------
>
> --
> |---------------------------------------/----------------------------------|
> | Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below
> |
> | first name lower case at ipal.net / spamtrap-2007-02-21-1645@ipal.net
> |
> |------------------------------------/-------------------------------------|
|
|
|
|
|