Magnet Definition and 868 Threads

What type of a magnet is really strong, not too big, durable, and has a long life? Where do I get it?

If I'm calibrating a magnet between 0.5T and -0.5T. Should I go to like 0.1, and flip the current to -0.1 then back to 0.1, onto 0.2, -0.2 etc. Or go in increments from 0T to 0.5 T, then 0T to -0.5T, after putting the magnet through a hysteris loop? I'd imagine the first way, but am wondering...

I have what is hopefully a quick question. Using only an unmarked magnetic bar and an identical metal bar, suggest a way to find out which is the magnet and which is the metal bar. This is supposed to be in a room with nothing but these two materials. Any help is greatly appreciated!

Hello, I am an engineering student doing my first real engineering project with a group of other engineering students. To give a background of my issue, I am charged with the task of designing a system which is able to detect when a rotating shaft spins too fast and send an appropriate...

The magnitude of the current depends on the rate at which the magnet is moving in and out of the solenoid. True or false

In lab, we used a bar magnet and a device that can measure magnetic fields. We put the measuring device near the north part of the pole and it measured 9T. We did the same to the south, but it gave us 75T. I was expecting it to give somewhere around -9T, is that what is suppose to happen? We...

This is a fairly simple question. I have some ideas of the implications but I have no idea what the total effect would be. My idea is to take an extremely powerful magnet. The strongest magnetic force that we can aqcuire. Then you take it into the vacuum of space and spin it so that north...

i know electrons have spin and charge which makes them the smallest magnet. protons also have spin and charge. does this mean they are magnets too with a north and south pole? Precisely where are these poles in relation to the spin axis of the proton and electron?

Hi, I'm considering working on something (vague, I know), but the whole thing hinges on whether or not it's possible to change the polarization of a magnet, and how. The basic premise is that I need two magnets which are attracting each other (so one positive and one negative charge), but I...

1)A thin rectangular magnet suspended freely has a period of oscillation of 4 seconds. If it is broken into 2 halves (each having half the original length) and one of the pieces is suspended similarly. What is the new period of oscillation? I solved it in the following way: Let E1 and E2 be...

Hi... I'm doing a solenoid for my project. But I don't know where to buy the magnet rod. I had look for a lot of place but doesn't have the magnet. Do anyone here know where can I get the magnet? Thank you.

at work, i was using a tool which is used to tight objects to each other, and after a while, i put it on the table, and small steel pins sticked to it. the steel tool, i guess that every time i tight the tool to the metalic objects there was friction, and somehow it became a magnet. and...

Hi friends, i have question will the magnet be able to stick to the steel ,when steel is at 150 degreee centigrade in same wave as it will stick to it at normail temperature. Please advice or give me the resourses to find magnet properties. Thanks Prashant Bidikar

will i damage my credit card if i put it on top of a strong magnet? i have a few smart cards together with my credit cards in my wallet. when i use my smart card (like a security access card to open doors, gates with electronic access) i tap my wallet on the reading pad which i believe is...

Lorentz force law tells us that workdone by magnetic force=0.Griffiths illustrates an example where work is done by the battery in a circuit.But I am intersted in something more.Who does the work of lifting some magnetic material when we use natural magnets?What is the way of energy...

If I were to take a permanent magnet and hold a piece of, say iron, a fixed distance away there would be constant attractive force generated between the two bodies. If I were then to cool the magnet down towards absolute zero, but keep the temperature of the iron constant, what changes would I...

I only have a vague idea of how the brain and MRI work but from my understanding the brain uses electric impusles and an MRI uses a huge magnet. Since a magnetic force redirects a moving charge, why doesn't someone go crazy when they are in an MRI because the neurons don't go where they are...

model for a flux pinning What is the best model we can make for a flux pinned magnet? From readings on superconductor levitation research (https://www.amazon.com/gp/product/0471559253/?tag=pfamazon01-20), I found that the magnet feels a spring-like force and that the spring constant (K)...

I recently particpated in a thread that was closed out before I got the answer to what seemed to me a kind of paradox A permanent magnet attaches to the side of a refrigerator. IT won't stay there forever , but it will for a very long time. All that time gravity wants to pull the magnet...

I am interested in building electric magnets. I have tried without success to find equations on what will make a stronger magnet. If I double the number of wraps, will the magnet be twice as stong? If I double the volts, will this make the magnet twice as strong? Does the type/gauge of wire...

I want to know that why magnet attract only metal but not all thing . Since all thing are made up of atom, what make the metal so difference so that it can be attract by a magnet ?

I want you to help me settle an arguement. Is it possible to have a center-pole magnet? That is, a magnet with one pole at the center, and the other pole facing out in every direction? I think that it isn't, because the molecules would force each other to all face the same direcion, or all of...

When a bar magnet (one with Npole n the other with S pole) is broken into 2 pieces, wat poles do the pieces have? thanx

Hey everyone, wondering if anyone knows if it's possible to remove the magnetism from a magnet through use of electicity. Specifically using 12volts, 2.5 amps DC. I'm looking for some kind of switch, or converter etc, that would remove the magnetism, but obviously I don't know exactly what...

if i were to shake a magnet fast enough, would i create light?, and if so which direction would i need to shake it? away then towards, up and down or sideways?

I am designing a three phase permenent magnet generator , and have a question. as a magnet pair passes over a coil , inducing a voltage, that voltage is most dependent on ? 1) the angular velocity ( that's a given) 2) the pole strength 3) flux density 4) energy product. 5) thickness of...

hi I was just thinking at school we learned that a current running through a coil of wires with a iron core produces an electromagnet. so if you place a bar magnet instead of an iron core would this strenghten the magnet or if placed in opposite direction render the magnet useless (given that...

Another poster is looking for a 20T magnetic field or better, so I went looking for what has been reported as the maximum field strength for an SC magnetic field to date. However I found some contradicting claims. Is there a refereeing organization or a reputable source from which to...

Question 1: Which type of free polarized electron (spin up or down) is attracted to the true North pole of a static magnet? Question 2: Why is a free electron attracted to or repelled by either pole of a static magnet?

Do you have any information about motion of magnet as it rolls down an inclined plane? Maybe some links. Or how to count the magnetic force which stop magnet? Thanks in advance

I'm doing some drawings on a cooling system, which includes a couple of so called "magnet valves". What excactly is a magnet valve, and does it actually have anything to do with the normal type of magnets?

I had a customer looking for some equipment that would be used in Europe to cool down a superconducting magnet that was to be installed there possibly in 2006. It must be an exceptionally massive magnet because he's looking for a very large cryogenic compressor and he says it will take 6 months...

Hi, I am making myself a humbucking pickup for my guitar and I need a bar magnet with poles running from one long side to the other (refer to http://www.rehandalal.com/magnet.gif" )... It needs to be a relatively strong magnet. So if anyone could offer any suggestions as to what material I...

Saw this gadget on tv that's supposed to change the taste of wine with a special magnetic field. And the new structure of the wine is to last for 15 days. Would this be possible at all?

Look at this figure. http://img223.imageshack.us/img223/2136/rotatingsuperconductorandmagne.th.png What will happen to the repulsive force between magnet and superconductor?Would the repulsive force increase with rotation?

Me and my buddy had a discussion the other day. Imagine the scenario with the donkey that has a danglin carrot in front of him. If we swap the donkey for a cart and the carrot for a magnet, what would happen? My buddy was pretty sure that the cart would move, and I thought that it wouldn't...

Hi: I'm having real trouble finding resources for the problem of accurately calculating (and drawing the field lines for) a magnetic field around a permanent bar magnet, or between two permanent magnets (I assume this is the same problem, as fields are superposable). I've found lots of sites...

I can't find any sort of charts for the stregths of different metals that i could use as the core for my Electro Magnet(EM). some plans for a E.M. would be kinda cool to see too if anybody has any. (also, this is my first post on this site and i am really excited because I've been lookin...

http://livescience.com/technology/ap_050729_super_magnet.html Does anyone know if there's anything bad about this? Some people on this other forum act like its the end of the world but its only about 21 tesla from another article. There saying you could rip out iron from peoples blood or...

Electrons inside of a solid matter spinning around their respective nuclei, with their axes quite parallel with the axis of that object, and that's how a magnet constantly supplies magnetic field (nice!). NOW: If I say that the magnetic field from a natural magnet is a mean of constant flux...

Does magnet wirealways have to be used in the production of solenoids or Transmformers?

what is the average size of a domain? and how are "permanent" magnets made? thanks, erin.

i have posted these questions in the chemistry forum but I have not receive any replys. Perhaps I have posted the questions in a wrong forum. why does the Earth behave like a giant magnet? why the hole in the ozone layer is above Antarctica but not polluted continents? in a fractional...

why does the Earth behave like a giant magnet? why the hole in the ozone layer is above Antarctica but not polluted continents? in a fractional distillating column of liquid air, the 'exit' of oxygen gas (b.p. -183C) is below the argon gas (b.p. -186C). However, when the liquid air...

Hello all, I have a ceramic doughnut magnet (from a speaker) and I'm wondering how to calculate its moment of inertia. I'm using a simulation program to do some mechanical analysis and I need to spin the doughnut magnet. It weighs roughly 185 grams, the inner diameter is 1.25in, the outer...

In a dutch forum I'm in discussion with a crackpot about extracting energy out of a magnet. He claims that when a iron object enter the range of a permanent magnet it need energie to become ferromagnetic. Is this really so and if it is where comes the energy from?

http://www.kgw.com/lifestyle/stories/kgw_020405_life_men_knit.715d1831.html I think this is absolutely terrific. Of course, some guys wouldn't think so.

I am having too hard of a time with such a simple magnet equation that I am starting to loose it. A particle with a mass of m carries a negative charge of - q. The particle is given an initial horizontal velocity that is due north and has a magnitude of v. What is the magnitude of the...

Can we please imagine that a sphere Neodymiun magnet with a diameter of one inch was suspended or leviated, reducing friction to none, then we put this magnet inside an acrylic tube that created a vacuum by pumping out all the air out allowing the sphere to spin at enormous velocity with very...

What is the maximum pull a normal magnet (non electromagnet) of about the size of a computer mouse could achieve? And how would the cost of this compare to the cost of an electromagnet of the same pull? Also, will an electromagnet achieve it's desired pull immediately when the circuit is...