Neekman99, IF you are trying to levitate a non-magnetized piece of iron or ferromagnetic material, like a little toy steel airplane, I believe you will find that the extremely fine balance between upward and downward forces will be almost impossible to achieve. The object will be pulled one...
"More coils which are not in phase will add to the electrical complexity - more rectifiers. "
@Merlin3189, Yes, the complexity is overwhelming me; the number of magnets and cores, the distance between magnets, the orientation of the magnets and their angles, the optimum rotational speed for...
Thank you Merlin3189. Yes, the no iron, no attraction, low torque was what I was thinking. Your reminder that the magnetic pull in force is equal on the approach to the iron core, and on the departure, may explain why permanent magnet only motors don't work. But BOTH of those attractions...
I would like to build, from scratch, a small generator to be driven by a small windmill, for experimental purposes.
One such generator on the internet has 8 NIB disk magnets (about the size of a quarter coin), flat sides facing out, mounted around a plastic rotor, with axes aligned along the...
Given a certain sized Savonius Wind Turbine, for example, using a 5 gallon bucket (about 12 inches in diameter and 14 inches tall) cut vertically in half, the standard configuration has the two "scoops" either touching at the central vertical axis, or partially overlapped.
Would moving both...
17:47 - dlbeeson:
Is there any benefit of setting capacitance of an LC tank to resonate an inductor at its natural physical resonance frequency, like a tuning fork frequency? Like a brass pipe hanging on a string in a wind chime, the inductor must also have some physical resonating frequency...
Graniar, so back to the original question, in an electromagnet, what core design will send the field out farther in 1 direction or axis? A long cylindrical core? A short fat cylindrical core with a pancake coil winding? A Cone shaped core with the point toward the washer to be picked up? What...
Electrical Review, volume 71 by George Worthington available here:
http://books.google.com/books?ei=6XcWUc-rOtPk2wWirYHwDA&id=tEFOAAAAYAAJ&dq=Electrical+Review%2C+Volume+71&jtp=887
on page 887 States "the absolute permeability of different substances varies in the case of magnetic materials...
I have FEMM and QuickField mag field plotting programs, but is there some simple interface like
http://phet.colorado.edu/en/simulation/magnets-and-electromagnets
but where you can change the core length and width by clicking and dragging, and change the coil turns and current similarly, and...
I have read that a magnetic field increases the permeability of the core. Is this true of an air core? If so, will a permanent magnet aligned to pick up the iron washer on the table, but not strong enough to do so alone, still increase the permeability of the air path from the electromagnet to...
Sophiecentaur,
Thank you again!
Yes, perhaps wireless is the long way around.
And of course you are right that wires are easier, and cheaper.
Yet, to be able to allow someone to just hang an aquarium on any wall, anywhere in their home, in any artistic arrangement does seem compelling to me...
Thank you for your response and help.
The Force is the magnetic pull force, in Newtons.
k is the permeability constant of air =µ0 = 4p×10-7 V·s/(A·m)
Found the formula here. I do note the response questions its accuracy.
https://www.physicsforums.com/showthread.php?t=662334
The original source...