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Electroboom: How Right IS Veritasium?! Don't Electrons Push Each Other??
bsfeechannel:
--- Quote from: Nominal Animal on July 22, 2022, 09:43:23 am ---One uses the steady state model, ignoring everything that happens when the circuit is formed, and then argues with someone who only looks at the initial nonequilibrium state or an AC system saying they are "missing the entire point".
--- End quote ---
DC is an engineer that came late for the transient.
SiliconWizard:
--- Quote from: Nominal Animal on July 22, 2022, 09:43:23 am ---
--- Quote from: Naej on July 22, 2022, 09:24:48 am ---What's the approximation here?
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Those arguing different places for the majority of energy flow are making different approximations.
One uses the steady state model, ignoring everything that happens when the circuit is formed, and then argues with someone who only looks at the initial nonequilibrium state or an AC system saying they are "missing the entire point".
It is useless to try and unravel the argument, until they come to a mutual agreement of an exact experimental setup.
They won't, because each one wants to keep their own approximations that let them define the originally vague and fuzzy system in terms that make their chosen answer stick. It's very, very silly.
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Yep. This was pointed out ages ago already and it just keeps going on.
cbutlera:
--- Quote from: SiliconWizard on July 22, 2022, 08:02:08 pm ---
--- Quote from: Nominal Animal on July 22, 2022, 09:43:23 am ---
--- Quote from: Naej on July 22, 2022, 09:24:48 am ---What's the approximation here?
--- End quote ---
Those arguing different places for the majority of energy flow are making different approximations.
One uses the steady state model, ignoring everything that happens when the circuit is formed, and then argues with someone who only looks at the initial nonequilibrium state or an AC system saying they are "missing the entire point".
It is useless to try and unravel the argument, until they come to a mutual agreement of an exact experimental setup.
They won't, because each one wants to keep their own approximations that let them define the originally vague and fuzzy system in terms that make their chosen answer stick. It's very, very silly.
--- End quote ---
Yep. This was pointed out ages ago already and it just keeps going on.
--- End quote ---
This brings to mind the interminable arguments that I witnessed many years ago on rec.bicycles.tech, about whether a bicycle stood on its lower spokes or hung from its upper spokes. Back then I almost invariably sided with the views expressed by the great Jobst Brandt - I wouldn’t have dared to do otherwise. But there are interesting parallels with this question.
When the wheels are turning, the path taken by the variation in the stress seems reasonably clear - the AC case. The spokes can be treated as if they are able to resist a compressive load up to a point, because the wheel is a prestressed structure. So up to a point, the spoked wheel behaves in much the same way as a disc wheel. But when the wheels are not turning, things are not so clear - the DC case.
It becomes even less clear if the stationary wheel is a disc wheel that may or may not have an internal pre-stress, and we have no way of telling. Once again it becomes essential to be very precise about the experiment, and exactly what question is being asked.
If the bicycle is inside a box being accelerated through space in a direction normal to the floor and is stationary with respect to that box, then to an observer in an inertial reference frame, kinetic energy appears to be flowing through the wheel. But what is the route that that flow takes through the wheel? Some would argue that it is passing up through the lower spokes, others that is is passing around the rim then down through the upper spokes. Another group may argue that the apparent energy flow is through the entire structure, and it is meaningless to be any more precise. A lone voice may then pipe up and say that since all of the relevant forces are in fact electrical, then every charge carrying particle in the box and bicycle is involved, along with many more outside. Who is right – everyone – no one?
A brick suspended on a string is hanging in a room. The string is attached to the ceiling with a suction cup that may or may not have adhesive on its suction face. What is the route taken by the force holding the brick in the air?
electrodacus:
--- Quote from: cbutlera on July 22, 2022, 08:57:10 pm ---It becomes even less clear if the stationary wheel is a disk wheel that may or may not have an internal pre-stress, and we have no way of telling. Once again it becomes essential to be very precise about the experiment, and exactly what question is being asked.
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The question I think is fairly clear.
How is the electrical energy delivered from the source (say a battery or charged capacitor) to the lamp?
To be even more clear a lamp is the same with a resistor or wire.
Derek take is that electrical energy travels from the battery trough that 1m air gap with his only proof being observing some small amount of current through the lamp in about the time it takes light to travel 1m.
He completely ignores the energy storage device formed by the transmission line.
Also is not about the distance from battery to lamp but about the distance from the switch.
Then there is absolutely no discussion about the steady state DC. At DC you do not even need to understand or acknowledge energy storage and you can not explain energy not traveling through wires.
In both cases DC and AC electric current travels through wires which means electrical power is dissipated in the wires and electrical power integrated over time is electrical energy.
Both the electric field (as found between the capacitor plates) and magnetic field around a stream of moving charged particles (what electric current is) are conservative fields meaning they do not radiate into space and you can not collect energy from that.
So is the same as magnetic field around a permanent magnet is always there and there is no way for you to extract any energy from that.
You can move the magnet or a wire around a magnet but that is converting mechanical energy into electrical energy not getting energy from the magnet.
The lumped element model perfectly describes what happens as seen by my spice simulation that got the same results Derek got in his real world experiment.
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