Electromagnetic Energy: Existence, Measurability & More

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Discussion Overview

The discussion revolves around the existence and measurability of electromagnetic energy, exploring theoretical concepts and hypothetical scenarios for energy extraction from space. Participants consider both practical and exotic methods of harnessing energy, including the feasibility of extending structures into space and the implications of such ideas.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants assert that electromagnetic energy is omnipresent and question its existence and measurability.
  • One participant suggests that the cost-effectiveness of energy extraction methods is crucial, highlighting the economic feasibility of various energy sources.
  • Another participant emphasizes the need to first assess the practicality of proposals, such as extending a pole into space, which is currently deemed impossible.
  • A participant raises a theoretical question about the application of friction in a vacuum, suggesting that if space is a vacuum, friction may not apply.
  • One participant mentions the crystal radio as a simple example of utilizing electromagnetic energy without batteries, drawing attention to historical methods of energy extraction.
  • Another participant elaborates on a hypothetical scenario involving a copper track around the Earth and a tether to the moon, proposing it could generate significant energy through the moon's motion.
  • Some participants discuss the concept of energy extraction from the planet's magnetic field, referencing real experiments conducted in orbit.

Areas of Agreement / Disagreement

Participants express a mix of agreement and disagreement, particularly regarding the feasibility of proposed ideas and the practicality of energy extraction methods. Multiple competing views remain on the theoretical aspects of harnessing energy from space.

Contextual Notes

Limitations include unresolved questions about the definitions of energy and friction in a vacuum, as well as the practicality of the proposed scenarios. The discussion does not resolve the feasibility of the ideas presented.

satelliteguy
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We are constantly surrounded by electromagnetic energy, right?
In what way does this energy exist? Is it measurable? Is there much of it?

Side thought, hypothetically, with a pole extended from Earth to outside Earth's atmosphere, couldn't the friction on the pole from "space" be converted into energy?
 
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satelliteguy said:
We are constantly surrounded by electromagnetic energy, right?
In what way does this energy exist? Is it measurable? Is there much of it?

http://hyperphysics.phy-astr.gsu.edu/HBASE/Waves/emwv.html

You might want to bookmark the whole hyperphysics webpage if you haven't discovered it already. There's a good possibility that some of your upcoming questions are covered in there already.

Zz.
 
Short Answer: Cost-vs-Benefit.

Long Answer: Sure, there are many available sources whereby energy could be extracted and converted to humanly useful purposes.
From the most mundane to the exotic, they are available. But, how much does it cost to do this?
If one spends a billion dollars to set-up a scenario that produces $1,000 worth of electricity per day, it would take 1 million days to pay for itself.

The science is not wrong, but economics must play a significant role.

Edit: Not talking about solar cells or wind energy here, rather more exotic approaches.
 
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Well, before you even get to cost/benefit, you have to ask if a proposal is even possible. Extending a pole/tower into space is not currently possible.
 
More of a theory, just wondering if even possible theoretically. If space is a vacuum, then is there anything to apply friction?
 
The most simple example of using eletromagnetic energy I can remenber now is the http://en.wikipedia.org/wiki/Crystal_radio" , an ancient radio receiver that needs no battery. Its power source comes from the eletromagnetics waves received from a long wire antenna, It was very popular in the early days of radio.
 
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TY dalespam, exactly the thought I came up w/ after posting my first thought of a pole. Maybe not feasible right now, but...
Next idea that followed, and is not practical, but a track made of copper, wrapping around an entire globe, laid out in relation to the moon revolving around the planet, and a giant tether coming from the track, and bolted to the moon. As the moon goes around the planet, it drags the tether w/ magnetic end and thus, produces constant energy. Not sure on the #'s for the math, but would certainly be an insane amount of energy.
May be feasible on a planet w/ few weather disturbances and a close moon w/ a quick planetary revolution. Now hook it up to a HUGE tesla coil, and voila, electricity for the solar system.

Or is that too far out for you guys.
 
russ_watters said:
Well, before you even get to cost/benefit, you have to ask if a proposal is even possible. Extending a pole/tower into space is not currently possible.

Exactly. Many things are possible yet not practical. Perhaps I had not expressed myself correctly. My post stands with corrected interpretation.
 
  • #10
satelliteguy said:
Side thought, hypothetically, with a pole extended from Earth to outside Earth's atmosphere, couldn't the friction on the pole from "space" be converted into energy?

satelliteguy said:
More of a theory, just wondering if even possible theoretically. If space is a vacuum, then is there anything to apply friction?

Well, I'm not quite sure I'd use the word friction, but there is the planet's magnetic field through which satellites pass. Even without the ability to build a beanstalk, there's some energy there for the taking. A number of real experiments have been done in orbit.

http://en.wikipedia.org/wiki/Electrodynamic_tether"
 
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