bumper cars anyone?
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Looks like the bumper cars caught up with the modern times. 
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Good one. 
Where were you when they got the idea to build the solar highway in France?
The fact that you criticize my railroad track like power supply system, but not the outrageously expensive inductive power supply idea which probably couldnât even be made to work, makes me think my idea could actually work!
Just because someone doesnât criticize one unworkable thing doesnât mean the other unworkable thing isnât unworkable. 
As for government funding development of out-there ideas, Iâm all for it. After all, if DARPA hadnât funded the development of ARPAnet, it wouldnât have evolved into the internet and we wouldnât all be hanging out on a Saturday morning talking cars.
Government funding led to the absurd idea of putting radio beacons in orbit and then using them to establish your location to within a few feet, and that enabled GPS which has been exceedingly handy to have.
There are two major driving forces behind most of the modern convenience technology that we enjoy. Government, which funds wild projects like an interconnected network of computers and electronic space-beamed mapping, and porn, which funds an amazing number of technologies we enjoy. Government gave us the internet. Porn gave us high speed internet. And VHS (one reason Betamax failed is that Sony didnât allow smut on their format, whereas it was freely available on VHS), DVD players, streaming video, etc, because all the porn consumers wanted a way to consume it without having to go to a blue theater in the bad part of town, and then they wanted more convenient ways to consume it, and they wanted to consume it faster.
And if you like being able to order things on Amazon and pay for them directly online rather than having to call a phone number or send in a check, you can thank porn for that too because people wanted an anonymized way to pay for their adult entertainment.
Given the choice, Iâd rather the government fund advanced development than the adult industry.
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I think you give a little too much credit to the porn industry.
People complained that government should spend money on earth than space, space flight research gave us much of what we enjoy today.
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Just to clear up a couple of misconceptions here, the coils have to have an iron core or the excitation currents required would be way too high. A lot of the early wall warts (small plug in power supplies that power small electronic devices and chargers) had air cores and their efficiency was horrible. A 10 watt power supply would use an additional 7-12 watts when plugged in and nothing attached. When you did plug in something, say a 5 watt load, it would require an additional 5+ watts to deliver. So a 5 watt load would use 17+ watts when on, 7+ when off.
China buys scrap core material from larger transformer manufacturers to make little core for these wall warts so they are more efficient now.
Anytime a coil is energized, it needs excitation current even when there is no load attached. An induction stove top would use a lot more electricity if it didnât have a variable voltage (temperature) and off switch like any electric stove top. When in off, no current is supplied to the core so it wont heat up any pan or pot no matter what it is made of. Once on, the current flow is minimal no matter the position of the temp control until a suitable pot is on top of he coil.
To heat a pot, the pot or pan has to have a metal that can be magnetized. Non magnetic materials such as aluminum or stainless steel simply do not work. Cast Iron, Carbon Steel and pans or pots made with either disc of regular steel or iron in the bottom or are multi-ply with one layer of magnetic stainless steel. Magnetic stainless steel has chromium but no nickel in its composition, I.e. 18-0 SS vs 18-10 SS.
Induction chargers are available to charge EVâs so the owner only has to park his vehicle over the coil, he or she does not have to plug it in. So in theory the charging roadway could work, but in practice, there are a LOT of obstacles in the way. It would probably cause a world wide shortage of copper. Then there are the issues like water intrusion, snow and ice, pothole damage just to start. But the biggest would be how would you meter the power consumed so the user could be charged for the power consumed.
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Well technically, it was the porn industry creating a product that people wanted to consume, anonymously and conveniently, that led to a greater societal demand for such things as on-demand video and high speed internet.
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Thanks for commenting about this. I donât know if youâre up for teaching me about transformer theory, but I donât understand why an aluminum or copper pan wonât work on an induction stove top. I know that iron has good magnetic conductivity, and poor electrical conductivity, which makes it a good choice for use in a transformer core. It helps direct the magnetic field through the coils in the right way maximize efficiency. But the coils in a transformer are copper or aluminum. It is these coils that create the electricity on the secondary winding. Wouldnât placing a coil of copper or aluminum wire on an induction cook top produce electricity? So wouldnât a copper or aluminum pan induct electricity and since it is shorted out, create heat? A shorted winding in a transformer creates a lot of heat. Or is my understanding that the pan on an induction cook top acts like a transformer secondary winding incorrect? Does the induction cook top produce a magnetic field in such a way that it is not intended to induce Voltage, but rather create a changing magnetic field that heats iron the same way core loss creates heat in a transformer?
Because they donât have magnetic properties.
What Cookware Works With Induction Cooktops? (thespruceeats.com)
Iâm going to do my best to keep it simple here. Ferrous materials that conduct magnetic fields, attract magnetic fields and concentrate them. Neither copper, aluminum or 18-10 stainless steel will do that. Copper and aluminum do conduct electricity though.
Because copper and aluminum are good conductors, meaning they have less resistance, not much heat is generated. Well some heat is generated but not like you see in ferrous metals.
The ferrous metals concentrate the magnetic fields and moving magnetic fields cause current flow. But since iron is not the best conductor, having high resistance, the current generated causes a lot of heat.
That is the short course, very short course. Core design in a transformer is far more complicated this isnât the place to go into that. The trick in a transformer is to concentrate the fields but minimize the current generated and thus reduce the heat greatly. Heat is losses and losses are not good.
Most residential transformers are 97% efficient or higher. Larger commercial transformers and sub station transformers run 99.5% efficient or higher. Those figures above are now required by law for transformers built after 2006 IIRC.
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Have copper wiring in for electric, and even had a mobile home with aluminum wiring for electric.
All materials have magnetic properties. Ones that work with inductive heating need strong, positive magnetic susceptibility. Iron is cheap and it would be the material of choice for this application. Paramagnetic materials develop weakly positive magnetic fields in the presence of an electric field and diamagnetic materials develop weak negative magnetic fields.
Even better would be battery swap or truck or rail car ferries to major destinations.
Yep, been driving one of those âbridgeâ cars for 15 years now. Expect to be driving it for at least another fiveâŠ
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