Is it posibble to transfer electricity wireless ?

[ngkamsengpeter]

I want to know whether it is posibble to transfer electricity wireless ?
Besides that , it is posibble to generate electricity from Earth magnetic fields ?

 

[Panda]

To your 1st question the answer is yes definitely...

Tesla 1st worked with the wireless transmission of electricity about a hundred odd years ago.
A couple of years ago a remote swiss village had a wireless power plant installed operating by transmitting a high power microwave signal from the nearest source of mains electricity into the village.
There are all sorts of health and effiicency (That sounds like a magazine title) issues with wireless power transmission that makes it impractical for normal use.

To your 2nd question the answer is Yes theoretically.
Wherever there is magnetic field you can extract electricity but as far as I know the extractable power is small and the cost of extracting it would be large.
There have been a number of schemes for extracting power from the polar fields but I'm pretty sure all of them turned out to be fundamentally flawed when it came to useability.

 

[haiha]

I've known that in some developing countries, people living near a radio transmtter station used to have a quite high antena, and then they can hear the radio with a special receiver without a power supply.

 

[russ_watters]

I've known that in some developing countries, people living near a radio transmtter station used to have a quite high antena, and then they can hear the radio with a special receiver without a power supply.

It is still a popular thing among hobbyists to build unamplified radios, called crystal radios: http://www.midnightscience.com/

Here's an interesting/innovative thing soldiers used to do, I found when we last discussed this issue: http://members.aol.com/djadamson7/articles/foxhole.html

You can pick up radio from lots of devices that aren't intended to pick them up. My company recently investigated an anomalous noise at a nearby hi-rise caused by a radio station transmitting from the next building. Computer speakers (amplified) would play the radio station without being connected to a radio. And you could hear it playing in the ductwork if you used an electronic stethescope (an amplifier).

 

[interested_learner]

Maybe someone can comment on this, but I heard that there is quite a potential difference between the ends on the Alaska Pipeline and if they didn't ground it along the way quite a current could build up.

 

[tim_lou]

of course yes! solar power plant is exactly wireless electricity... wireless power from the sun!

 

[ngkamsengpeter]

I have another interesting questions , if there are extremely high current combined with the Earth magnetic fields, then there will be magnetic force that will acting on the body . If in right direction , the body will fly .right ?
Besides, I heard that the human body also using electricitcity to transfer bio-signals to brain , then it is possible to calculate the current and the magnectic fields on the the certain part of the human and also the magnetic force act on certain parts of human body ?