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Q & A: Novel electrical power transmission idea

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Most recent answer: 10/22/2007
Q:
Would it be possible to charge a super small metallic object then use something to throw it across a room to something that could catch it and then intern supply power to that object?
- Patrick (age 16)
Tennessee
A:

Sure, I guess you could do something like that, but there are some things to think about which could limit the usefulness of this approach.

We could think of a steady state where a machine which can charge up the metallic objects constantly supplies them and throws them across the room, and the power consumer across the room consumes a constant amount of power for a long time -- this is the usual way light bulbs work, for example. The problem then is that you have to get the small metallic objects back to the power station so they can be re-used. Furthermore, the electric charge should also go around in a complete circuit, otherwise a net charge will build up on the power consumer (and an opposite one on the power station). This can be fixed by running a wire across the room, connecting the power consumer to the power producer.

If you send the electric charge back on the small objects by throwing charged ones back across the room, then energy cannot be extracted from them (they go back in the same state they came). There are two ways around this. One I already mentioned, is the idea of running a wire (but then why not just run two wires, one carrying the charge out, one carrying it back, as it is usually done?). The other way around this is to make your little charged objects carry equal amounts of oppositely-signed charge. This can be done if your small objects are capacitors. Capacitors store energy by having a charge on one plate which holds in place an equal, opposite charge on the other plate by electrostatic attraction. The plates have an insulating material between them so the charge cannot simply flow to cancel it out. If you connect the plates of a capacitor together on the consumer's side via a light bulb, you can extract the energy from the capacitor as charge flows off one plate, around the light bulb, and onto the other. You can then throw back the discharged capacitors to be re-charged.

Tom


Tom has just suggested that " if the goal is to deposit a net charge, or to provide a small current at very high voltage, like a Van de Graaf, then his idea has a lot of merit." He's provided this link : http://www.pelletron.com
Mike W,

 


(published on 10/22/2007)

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