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think tank

think tank

think tank

(OP)
Hello I have two questions that have been bugging me.

Here is the situation that involves power generation. Let's say a magnet is spun with a wire coil surrounding it ( a typical generator) in a vacuumed container in freefall ( such as satellite orbiting earth). Wouldn't this create a virtually unlimited source of power until friction caused by subatomic particles stopped the magnet?

Another question. Why are electromagnetic motors used more frequently than electrostatic motors?

I have tried to find the answers to these questions everywhere to no avail. Any input is appreciated

RE: think tank

Two easy answers:

1 You brake the magnet when you exract power from the wire.

2 Some electrostatic MEMS motors have been built. Microwatts of power there. More torque from electro-magnetic systems.

3 Accept that there is no free energy.

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: think tank

Quote:

1 You brake the magnet when you exract power from the wire.
Otherwise, even here on earth, the prime mover (engine) would only have to furnish enough power to overcome friction.
 

RE: think tank

Is that another form of a perpetual motion machine???

There are already some prototype flywheel systems where the flywheel is in a vacuum and uses magnetic bearings. They will spin almost indefinitely until power is extracted. Someone was experimenting with using one in a hybrid car instead of batteries. But then, maybe there are some commercial versions of these around by now.

 

RE: think tank

There are plenty of commercial flywheel devices on the market. They are used as storage for uninterrupable power supplies. No legitimate manufacturer (or anyone else that understand the laws of physics) promotes them as perpetual motion machines.

http://www.liebert.com/product_pages/Product.aspx?id=59&hz=60

RE: think tank

The flywheels of rotary UPSs slow down so much that something has to be done to maintain nominal frequency.  One brand uses disk drive type technology to dynamically "write" magnetic poles on the surface of the flywheel so that the number of poles continuously increases to maintain nominal frequency as the wheel slows.

RE: think tank

That's weird since all the energy is up at the high RPM. E=U2

Can't imagine that being worth the effort.  Most put out DC and invert to AC or put out whatever, rectify and invert.

Keith Cress
kcress - http://www.flaminsystems.com

RE: think tank

To sum it up - I believe the original poster needs to read up on the law of conservation of energy.
 

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