How to make your own magnet
First, you need an object that can be magnetized. Wood or glass, for example, cannot be magnetized. Any material that can be magnetized is called ferromagnetic ("Ferro" meaning containing iron). "Soft" ferromagnetic materials will lose their magnetism once they are removed from a magnetic field, while "hard" ferromagnetic materials, such as iron, retain their magnetism. The only three elements that can be permanently magnetized are iron, nickel, and cobalt. Some elements, such as chromium, exhibit paramagnetism, which means they can only be made into weak magnets.
To make a magnet out of a piece of ferromagnetic material, you must place the object in a magnetic field. As the field cuts through the object, most electrons within the material are aligned in a similar orientation, and the object becomes magnetized.
An object can be influenced by a magnetic field in one of two ways. The first method is simply to stroke the object with a piece of metal that is a known magnet. Take the magnet
and identify it's two poles (north and south). Label the two poles with a marker. It does not matter which is north or south, just that the two ends are the poles. Orient the other object so the longest axis is in the same direction as the magnet's poles. Then, swipe one by the other, like so:
Make sure to always go in the same direction, and never stop over the object. Always do clean swipes from before the top to after the bottom (pull it all the way off in the same axis, not apart). After 100-150 strokes (number varies depending on the strength of the magnet), the object will have a weak magnetic force. It probably will not last longer than a few hours.
The other option is to put a strong electric charge through the object. An electric charge causes electrons to flow in the same direction. The reason why magnets work is that the electrons are in the same direction, so this is a way of orienting them. When you make a magnet in this manner, its called an electromagnet. An easy way to make an electromagnet is to use an iron nail (3-4 inches long), a battery (AA or 9v work best), a coil of wire, and a resistor. The easiest way to find an iron nail is to see if it is rusting or not. A rusted nail has iron in it. Mark out 3 inches of wire from the end of the spool, and place the head of the nail on that spot. Use the rest of the spool (not the 3 inches) to wrap the nail from head to 1/2" from the point. At the end of the wire, mark off another three inches, and cut the wire. It should look something like the following:
|-| <- wrapped wire
| | <- 1/2" uncovered near the tip
Then, attach the resistor to one end of the wire. This serves to restrict the electricity
, and keep the battery from short circuit
ing and exploding in your hands. Connect the other end of the resistor to the battery, as well as the other piece of wire. Place the tip of the nail near a paperclip
, and if all went well, you have a magnet! Try removing the battery, then picking the paperclip up again. The paperclip doesn't move. This is because the nail is a soft ferromagnet. It will not remain magnetized unless something else (the coil of wire) is forcing it to. Cool, huh?
More about magnets:
In recent years, scientists have come up with a number of alloys to produce small, yet extremely powerful, magnets. "Rare Earth" magnets are so strong that once you stick one to a butter knife, it can never be moved. Ever. The strength of the bond is so great that it has essentially welded itself to the knife. Another alloy, alnico (a mix of aluminum, nickel, and cobalt) is stronger than the Rare Earth magnets.
The earth is one giant magnet. A compass helps us find directions because it points to Earth's magnetic poles.
Today's computers would not be possible if not for magnets. The memory and storage devices, such as hard drives, tape backups, floppys, VHS tapes, etc, use magnets to record data. (CDs and DVDs are an exception here)
More than half of the worlds magnet supply comes from Japan.
The ancient Chinese and Greeks knew about rare and mystical stones with the power to attract iron. These were natural magnets of iron-rich ore called "lodestones." This was the only form of magnetism known until 1821, when science proved magnetism was not a magical force.
The first Greeks to discover the lodestone lived near the city of Magnesia. This is where the word "magnet" comes from. Milk of Magnesia was also discovered in Magnesia, but has no relation to magnets.