Once again, I was wrong in my assumption. :) I'm learning though.
I read somewhere about current, and it was explained just like you said it, it's the measure of the number of electrons that pass a given point. It seemed to me that since the electrons go back and forth, you would have a net movement of zero. I know that there is a small drift of electrons, but surely we wouldn't be measuring that and calling it amperage right?
with
caused
enough
though.
movement.
given
like you said it,
given point. It
would have a
the net *movement is zero.,, but the net *force imparted to create that movement is absolutely energetic..force is required to create the movement..and force via use of an electric motor can be extracted from that movement.
On both ends please notice its phsical torque that turns the generator..and with a motor out put shaft to gear drive that crushes rocks... its physical force out as well.
I know that there is a small drift of electrons, but
right?
sure its amperage... its just going back and forth is all.
Phil Scott
Brian Dugas wrote:
No, electrons do flow. It doesn't matter if there is 'net' electron flow, that is, they can transfer energy by move back and forth as easily as by moving in one direction.
No, in fact current is determined by the number of electrons that pass a given point at a given time. They move, either (relatively) slowly in one direction in the case of DC, or (relatively) slowly back and forth in the case of AC. The movement of the electrons at their drift velocity is exactly electric current. EMF is voltage. It is analogous to a pressure. When there is a voltage between two points at a certain distance apart, there is an electric field (volts/distance). When there is an electric field in a conductor, there is a net electron movement, or a current, which is proportional to the electric field and inversely proportional to the resistivity of the material. Whenever electrons move, they must move in a circuit, because they can't accumulate at any point (let's not bring capacitors or van de graff generators into it). When the electrons move in a circuit, there is an electric current. The power dissipated in the circuit is equal to the voltage times the current. Now, let's look at your phrase 'EMF passes a point'. Voltage changes do move through space, at the speed of light or close to it, but that is not electric current. Here's an analogy. Imagine a train, with cars extending for one mile. The engine starts moving. The last car in the train doesn't start moving instantly. There is a certain amount of space in each coupler, and stretchiness to the metal parts, so that it takes some small time for the last car to start moving. If you were standing next to the train, you might hear a clicking sound moving rapidly down the train, as successive cars began to move. The pressure from the engine to accelerate the cars finally reaches the last car, and a force is felt at its coupler that begins to move the car. In this analogy, the voltage is the pressure applied by the engine. The rapid transfer of this pressure from the first to the last car is the propagation of the voltage change at close to the speed of light. The movement of the cars is current.
-- john
Very great analogy there with the train. So let's use a 1 amp circuit for example. How far do the electrons move per second? About 1 inch? How can an amp meter detect this? I always thought the amp meter detected the EMF. Didn't someone say that the higher the voltage, the bigger the EMF is? But that still doesn't correlate to current, so that can't be it. I'm just amazed that a meter can detect electron movement when it moves at such a slow rate.
I guess you are trolling, after all. If you aren't, you need to forget what you think you know, and read a book.
-- john
Not sure what you mean by trolling. I only use that term when discussing fishing. But I do plan to read some books. I don't work in the field of electronics and don't plan to. I'm a software trainer by day. I'm just fascinated by certain things. I appreciate all your help John. Brian
And that isn't 'at the power company'. All the large scale generators I've worked with have used grounded neutrals. Transmission lines are often neutral grounded wye (gives higher line-line voltage for given step-up transformer and avoids voltage to ground balance problems).
High energy photons that spontaneously form an electron-positron pair is called 'gamma pair production' and has nothing to do with commercial electrical systems. The energy the photon must have to form such a pair is quite high and (hopefully) not something found in everyday sunlight here on earth. Something like 1.2 Mev or higher, also known as a gamma radiation.
Photovoltaic systems do not 'create' electrons from photons in the sunlight. The energy of the sunlight merely frees the electron from the atom it is normally bound to.
daestrom
message
my
the
did
typical 3
generators I've
are often
given step-up
electrons
the
electron-positron pair is
commercial
I did NOT say it did....I said these electromagnetic spectrum manifestations change form as a matter of course routinely.. they materialize and de materialize...our fixed notions because are information is so limited are in error...and calculate only by including these conversions where they occur
The energy the photon must have to form such a pair is
sunlight here on
Look, I dont want to be abusive nor to be abused by having my valid arguments countered with smoke. On the issue you raise above you might wish to consider the photo electric cell. Photon energy is directly converted to electrons..DC.. not AC that can be said not have been created but just jammed back and forth...but DC... that is actual electrons. you can research that easily.
Something like 1.2 Mev or higher, also known as a gamma radiation.
oh please.
in the sunlight.
the atom it is
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