what are magnets used for? Homework question?
923117
To create an electrical current, and to affix nice pictures and notes to refigerators.
114658
Get a magnet and try it.\n\nRead the last sentence of the link below:
84144
You need to define "effect".  It also depends on the strength of the magnet, but if you're talking about something like a fridge magnet or something like that it's a very small fraction of an inch before the effect is negligible.
839068
I've already answered this question and you might want to refer to that for more details. But here goes. \n\nA magnet is made of ferromagnetic materials, and will only attract ferromagnetic materials. These are iron, nickel and cobalt. Any alloy that contains one or more of those is ferromagnetic.\n\nThe metal forms tiny grains as it cools from a liquid to a solid, and within these tiny grains are even smaller regions called magnetic domains. Think of groups of atoms packed together. Unless a material is abolutely pure, there will be odd atoms of other elements and when the metal cools, they do not stack together absolutely correctly. If it is only a tiny amount of impurities, we do not notice the difference in terms of size, shape or weight.\n\nBut the domains are not lined up the same. Think of a bunch of guys just starting basic training. They are all milling around on the parade ground. But let's say that we heat the bar of metal until it is almost ready to melt and then subect it to a strong magnetic field (stick it inside the coil of a strong electromagnet, and let it cool that way.)\n\nNow they are all lined up the same way (just the way a bunch of paper clips will al line up when you pick them up with a magnet.) And when the metal cools and become solid once more, now they stay in that position. It is like a drill sergeant coming and yelling at the new recruits until they line up in formation. Now they are ready to take orders and get some useful work done.\n\nWhen the troops all line up and march the same way, you can see the result. They are more orderly, when they march along their feet all hit the ground at once, and they look unstoppable! \n\nIt is the same way with the magentic material. Each one of the individual atoms has its own magnetic field, but when they are all pointing in random directions, nothing useful can be done. Some are pointing one way, some the opposite way. They act against each other and their corporate effect cannot be felt.\n\nSo, now that the atoms within the domains are lined up together, and the metal has cooled and solidified into a solid bar again, the domains are lined up in formation. Now, they are all pointing in the same direction and we can feel the effects of the magnetic field even outside the magnet itself. The magnetic field reaches beyond the magnet and loops around in space until it reaches the other pole, forming a sort of circuit.\n\nOkay, now we have a magnet and we can understand why it attracts another magnet, because opposite poles attract. north attracts south and south attracts north. (No such thing as gay magnets! it's a law of nature!). \n\nBut why does it attract ordinary non-magnetized iron or steel?\n\nThat has to do with the fact that even though the metal is solid, and the atoms cannot flow away as in a liquid, the atoms are still free to rotate in place without moving from where they are.\n\nThink of the group of raw recruits before they go through their basic training. They are standing around. All of a sudden, they hear a loud noice. It is the drill sergeant yelling at them. All their heads turn in his direction! He has their attention. It is the same way with a magnet.\n\nWhen the magnetic field of a magnet acts on the atoms (iron, nickel or cobalt) of a piece of ferromagnetic alloy that has not yet been magentized, even though the atoms can't move from their spots, they rotate to face in the direction of the magnetic field. They temporarily act together, just as the domains inside the permanent magnet do. The fancy scientific name for this is 'magnetic induction'.\n\nNow, the temporary (induced) pole in the piece of metal is attracted to the permanent pole of the permanent magnet. They move together, because the tendency is for the magnetic field to travel as short a distance as possible, and a pole alwasy induces the opposite pole. The two together, so the magnetic field can travel across the shortest possible distance.\n\nWhen the
1070520
Try this. Iron when combined with other metal elements becomes non-magnetic, yet with varying of the same elements is quite attracted to the magnet.Name the divisions of the metals and explain why.
485205
a magnet by definition is a LINEAR entity consisting of 2 opposite ends ( north and south ).\n\nif you cut a rectangular magnet into a smaller sphere, that linear axis in the original magnet will still stay the same in the sphere !\n\nmagnets ALWAYS have a linear alignment no matter there exterior shape !
805479
Get two pieces of iron block. Turn a coil round one of them. Pass electric current through the one which has the coil turned round it. This will make the coiled piece of iron act like a magnet and will attract the other piece of iron. And you have made an electromagnet.
198626
You could measure the strength of an electromagnet by hanging small iron \nweights from the magnet.  When the applied weight (force of gravity acting \non the weights) exceeds the force of the magnet, the weights will fall \noff.  Steel Flat washers of the same diameter as the coil would be \ninexpensive and simple to use.  You can weigh several washers on a food \nscale and calculate the average weight of each washer.\n\nThe equation for the magnetic field strength, H0, in Ampere-turns per \nmeter for an empty (air) coil is:\nH0 = the applied voltage / (the number of turns of wire in the coil \nwinding X Area within the coil winding X the permeability of air).\nThe area is pie X D squared/4, where D is the diameter of the coil winding \nin meters.\nThe permeability of air,  , is 4 X pie X 10 to the - 7  henry/meter\n\nThe Equation is for a direct current.  An alternating current applied to \nthe coil cannot be used for lifting magnetic objects.  \n\nBy substituting different numbers for the applied voltage, the number of \nturns of wire and the diameter of the coil, you can calculate how each \nparameter will effect the strength of the magnet.\n\nElectromagnets can be fun, however,  keep them away from recorded tapes or \nthey will erase the contents.
1162143
the magnets somehow circulates your blood.  The higher the #, the better they work.  But someone told me that it didnt really do anything for him.  Good luck
997877
that's sweet here i think is a link for a patent. I was thinking on how to make something like that, accelerating itself but i failed :P another of my questions was proven wrong leading me to the conclusion it is impossible for magnets to be used in mine.\n\nhttp://www.inventhelp.com/contactform_patent.asp?id=106&wcw=overture&GCID=S17330x002&KEYWORD=patent+office&MATCHTYPE=search
52641
A material which is predominantly diamagnetic will be repelled by a magnet, although typical objects only feel a very small force. This can be used to levitate light pieces of pyrolytic graphite or bismuth above a moderately strong permanent magnet. As water is predominantly diamagnetic, this property has been used to levitate water droplets and even live animals, such as a grasshopper and a frog.
1029513
has to be metal, preferably in several sheets not touching each other. Wood and plastic do not stop magnetic field.\n\nThick piece of lead would definitely work, and is completely safe (as long as you do not drop it on your foot and wash your hands afterwards)
121288
The basic idea behind an electromagnet is extremely simple: By running electric current through a wire, you can create a magnetic field.\n\nBy using this simple principle, you can create all sorts of things, including motors, solenoids, read/write heads for hard disks and tape drives, speakers, and so on
131722
OK, so it's a little confusing to me, but apparently the magnetic pole close to the north pole is actually a south magnetic pole.  So for some strange reason, the north pole of a magnet bar will be attracted to the south magnetic pole which is located near the north pole.\n\nNorth poles on a magnet are very easily found.  When you bring a magnet up to a coil, and move the north pole back and forth, you will get a current flow in a particular direction (counter clockwise).  \n\nIf you wish you can create your own magnet.  This way you can decide which end is north, and see which end points north.  You need to pass current in a counter clockwise motion.  Use your right hand and make a thumbs up sign.  Your fingers are pointing in the direction of the current, and your thumb is pointed in the direction of the north field.\n\nBest way is to take a wire and wrap it around a bolt at least 10 times.  Current leaves a battery on the positive terminal and enters the battery on the negative terminal.  Make sure you keep track of the direction of current flow.  Then use the right hand rule I indicated above.  The thumb shows the direction of the north magnetic pole.  I wish I could draw you a diagram.
361293
Do you mean "magnetic"?????
202402
A long straight coil of wire can be used to generate a nearly uniform magnetic field similar to that of a bar magnet. Such coils, called solenoids, have an enormous number of practical applications. The field can be greatly strengthened by the addition of an iron core. Such cores are typical in electromagnets. \n\nSolenoid Field from Ampere's Law:-\n\nTaking a rectangular path about which to evaluate Ampere's Law such that the length of the side parallel to the solenoid field is L gives a contribution BL inside the coil. The field is essentially perpendicular to the sides of the path, giving negligible contribution. If the end is taken so far from the coil that the field is negligible, then the length inside the coil is the dominant contribution.
56297
elements fall under one of three categories: stuff that is always attracted to a magnetic field, stuff that is always repelled by a magnetic field, and stuff that can be magnetized ei you can make a magnet out of it. For example, water (yes i know its not an element) is always repelled by a magnetic feild, titanium is always attracted and iron can be magnetized. To see the effects of water being repelled by a magnetic field, buy some neodymium magnets, (the bigget the better) and place it in a bowl of water so that the magnet is barely covered with water. place it in front of your compurer screen, and look at the reflection of the computer screen in the water just above the magnet. you will notice th reflection is warped just above the magnet.