2007-07-27 10:08:48 · 10 answers · asked by ballineagles 1 in Science & Mathematics ➔ Physics
TRY RARE EARTH MAGNETS THEY ARE THE STRONGEST
IF YOU HAVE AN OLD HARD DISK DRIVE, IF YOU TAKE IT APART, THERE IS A PAIR OF THEM THAT CONTROL THE HEAD POSITION
YOU CAN STICK ONE ON THE PALM OF YOUR HAND AND HOLD IT IN PLACE BY STICKING THE SECOND ONE ON THE BACK OF YOUR HAND
TAKE GREAT CARE NOT TO TRAP YOUR FINGERS, THEY ARE VERY STRONG MAGNETS!!
IF YOU MUST MAKE A MAGNET, WRAP 40 TURNS OR SO OF BELL WIRE ROUND A LARGE COACH BOLT AND ATTACH THE ENDS TO A 6VOLT LANTERN BATTERY
DO NOT USE RECHARGEABLE BATTERY TOO MUCH CURRENT WILL FLOW, MELTING THE INSULATION ON THE WIRE
DO NOT LEAVE CONNECTED TOO LONG THE BATTERY WILL GO FLAT QUITE QUICKLY
2007-07-27 10:22:42 · answer #1 · answered by andy t 6 · 0⤊ 0⤋
I'd not try the electromagnet approach unless you are ready for a lot of work and relatively disappointing results. The electrical relay folks use these and they don't get a really strong field even with 100s of turns.
The rare earth magnets are the way to go - even if you have to buy them (it will be cheaper than all the wire and batteries etc for Electromagnets).
One of these NdFeB (Neodymium - Iron - Boron) at 1/2 inch thick (6mm) can deliver a tesla on the face (4000 guass) and stick to your refrigerator so hard you'll scratch the paint getting it off!
If you go the extra mile to make a "pole piece" for this magnet, a 1/2x1/2x2 inch can lift over 50lbs. The pole piece is a U shaped steel plate that the magnet fits into. Hard to demo without a picture.
2007-07-27 17:43:28 · answer #2 · answered by bubsir 4 · 0⤊ 0⤋
A coil of copper wire through which a current is passed. The strength of the resulting magnet will depend on the square of the amount of power lost in the wire due to its resistance; you can choose the wire size to take a small current at high voltage, or a larger current at low voltage. It will be obvious that for really strong magnets, the power requirements will be huge; that is why magnetic resonance imaging machines (which require a very large field to work properly) use superconducting magnetic coils which have to be cooled by liquid helium. Which is expen$ive.
2007-07-27 17:27:58 · answer #3 · answered by Anonymous · 0⤊ 0⤋
You could make a pretty good electromagnetic with a car battery, some magnet wire, and an iron or steel rod.
2007-07-27 18:45:34 · answer #4 · answered by Dr. R 7 · 0⤊ 0⤋
A long'ish and very pure iron core that tapers to a narrow point. Wrap it several thousand times with very fine, very pure copper wire that is as neatly placed loops (all along the length of the core, except for the tapered part) as you can humanly get.
Send a current thru the wire and you have a pretty decent 'size' electro-magnet.
2007-07-27 17:16:45 · answer #5 · answered by Anonymous · 0⤊ 0⤋
Find a magnet with more mass. It works.
2007-07-27 17:15:54 · answer #6 · answered by Mod Candy 3 · 0⤊ 0⤋
With super conducting material. You'll need helium and stuff which is difficult to get!
try different shapes/types of ferromagnetic material. Not sure what influences the strength here.
2007-07-27 17:19:46 · answer #7 · answered by mic 2 · 0⤊ 0⤋
The strength of an electromagnet is proportional to its ampere-turns, that is the product of the number of turn of wire and the current flowing in the wire.
2007-07-27 17:40:32 · answer #8 · answered by Renaissance Man 5 · 0⤊ 0⤋
The easiest way is to find your grandpa's RCA radio in the garage and extract the magnet from its loudspeaker.
2007-07-27 17:22:32 · answer #9 · answered by Alexander 6 · 0⤊ 3⤋
A lot of continuous strong friction.
2007-07-27 17:11:12 · answer #10 · answered by E 5 · 0⤊ 3⤋