|MadSci Network: Physics|
"The birth of an idea is a happy moment in which everything apppears possible and reality has not yet entered into the problem," sayeth Rudolph Diesel many years ago. Possible, probable, practical: It is certainly possible to radiate information. We've been doing that since Marconi invented the AM radio. So it is possible to transmit power through the air in the same way Wi-Fi transmits information, but it is not practical to transfer, say, enough power to run the fan on a desk-top computer. Radiating appreciable power is wasteful. Energy radiates from an antenna, or from the Sun, in all directions unless constrained somewhat by the shape of the antenna dish. Even then, large amounts of that energy can and will be absorbed by the air, far more than would be absorbed when wires are used to transmit power. Have you ever noticed that the air inside a microwave oven that's been run for a while is hot? As for designing such a system, [i.e., the min volts, min watts, min distance, etc.], since it's never been done, it would require what's called a "Developmental Program." That means that you guess at those parameters and go with trial-and-error until you find the combination that works best. That's a lengthy and expensive process much like what is done in developing a new drug.
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