Electromagnets Definition and 87 Threads

Hi all, i was wondering if you could help me calculate a few things to do with induction and electromagnets. I wanted to look into energy harvesting or charging using electromagnets and wanted to know how to calculate the energy that is created from this product below...

I'm looking for a good source of information on electromagnets. Does anyone know a good source?

Hello; Just a question that I have been thinking about. Is there some reason why they wouldn't work in water? Thanks.

Homework Statement What is something other than a battery that I can use for an electromagnet that won't lose power and you can pick how many volts you want. Homework Equationsnone The Attempt at a Solutionnone

Many real motors use electromagnets to create the magnetic field that causes their rotor to spin. Give one advantage and one disadvantage of building a motor which uses electromagnets rather than permanent magnets.

Hi everyone, I was wondering a little about superconductive electromagnets. Somewhere, I heard that Carbon Nanotubes had special properties, one of which is that they're superconductors (something to do with some quantum effect or another). Anyways, I was wondering, could you make a...

anyone have equations for bitter magnets? or do i use the ones for solenoids? i need an electromagnet capable of 4T. that doesn't use super conductors >_> i have access to liquid nitrogen though.

Right, I'll try to get this question across. Say you have 2 bar electromagnets, aligned so when you turn them on they are attracted to each other. You start with them touching, turn them on and pull them apart. You then turn of the current and put them back together. If you continue to repeat...

I was asked to design and build an electromagnet that generates a magnetic field of 2 T. I find it a good idea to have a look at the specs of such magnets made by specialized manufacturers to help me to choose the required type of iron. I searched for information (data sheet or specs) using...

I am trying to conduct an investigation based on the set up of a set of copper coils with AC ran through them to make them an electromagnet. Held above them inplace is an aluminium plate. I know that the changing magnetic field induces a current in the aluminium plate, which induces a voltage...

Where can I buy some dees (aside from acquiring them at a university)?

Hello all, I am a computer science graduate who has gotten involved in robotics a lot lately. I am finding myself getting more and more mechanical/physics related questions in my mind, such as this one. The question is: I know how to create an electromagnet by wrapping a big wire around a...

I want to know about the FORCE BETWEEN TWO ELECTROMAGNET OF RECTANGULAR CROSS-SECTION. The force due to the fluxes both direct face to face and radial seperately. Also I like to get the exact formula or the source from where I get that. Can anyone help me? pls.

Hi, This is not homework, I'm just confused: I have been asking on the electrical engineering forum about calculating the strength of electromagnets. After some searching i have found the equations but i just can't quite get a handle on some of it? They have an iron core C shaped...

I need to caculate the Pull in LBS of Electromagnets, i am missing some information regarding this & maybe some brain cells also. B (Flux Density)= Flux Lines/ Area Pull in LBS= B x A / 72,000,000 Ok, how do i get B Flux Density in lines per sq/inch for the calculation. I guess it...

I'm looking to get a full understanding of what makes them work, any suggestions for some one not so familiar with the subject.

I'm doing an independent study for high school, and my project is to build a wheel motor such as the one pictured http://www.popsci.com/files/imagecache/article_image_large/files/articles/hiw_hybrid_infog_485.jpg" (though less complex, obviously). Essentially what I'm trying to do is to make an...

Hi, I need to grasp an understanding of how electromagnets work in a maglev train system for my senior physics research task but I am having trouble understanding what the sources I find are saying. I was wondering if anybody would be able to explain how the electromagnets make the train...

Hello, Let's say I have a neodymium magnet with 20 lbs of force, and an electromagnet with 200 lbs of force. Is there a way I could figure out the maximum distance that they would attract each other?

Hello everyone, I am writing with a strange problem. I have been attempting to make an electromagnetic coil that will have enough power to pick up say an average 9v battery in weight, the small kind found in the back of telly remotes and smoke alarms. I am using iron bolts 5cm long by...

[SOLVED] Electromagnets and switching polarity? Hi people, I am relatively new to the forums and am experimenting with a new toy I want to try to make. I am stuck on the subject of changing polarity quickly in an electromagnetic coil and automatically. Let me explain. I have two rubber...

Hi everyone Im an engineering student currently working on a group project. Part of the project is to use a electric magnet and a permanent magnet to balance a weight on the end of a cantilever (digital scale effectively). We would then measure the current through the electromagnet to...

I read a couple of tutorials on electromagnetism and solenoids but there's a good few questions left unanswered. 1.) What determines the poles of a solenoid electromagnet? Let's say I have direct current flowing from the left end of the coil to the right. Will the north pole automatically be...

I will keep this brief a tattoo machine is basically an old fashioned doorbell. to coils wired together with a resistance of 2 ohms, generally a 47uf 50v electrolytic axial capactior. the contact is a spring and copper screw. the circuit opens and closes rapidly, 105hz to 145hz. my question is...

Allright, I'm only 17 and I have some questions about electromagnets. Okay, say I have an electromagnet that had a holding value of 1700lbs. when there was no gap between the magnet and the metal object. My question is would this magnet be able to pick up the metal object if it were around 4...

Hi, Would an electromagnts or solenoid behave any different if a permenant magnet was attached to it when it is powered up? For example, if I had a opposing pole type electromagnet and I attached the north pole end of a permenant magnet to the north pole end of the unpowered electromagnet. Now...

I was wondering what the reaction would be if you aimed RF signal/s into a high powered circular electro-magnet (i think the proper term is a toroid ?). I ask because its too dangerous for me at the moment to conduct experiment. (220v @ 20amps). would the signal be shot out the side that has...

I'm constructing an typical electromagnet, wrapping coil x amount of times around a 1" diameter iron bar, and getting power from 'D' cell batteries. My question is how thick can the wire's insulation & jacket be? Most of the examples I've seen used a nail, with 22-26 gauge copper or magnet...

Okay, I have been looking the web over for some toroidal (doughnut) electromagnets for a project I am working on. Any ideas on where to get some? I need about 8 to run off of 110 VAC (10A) or 12 VDC (220A). Inductive force is not important. Inner OD should be about 3 inches or so. Danke (no...

Hey there, I am studying the effect of current on the strength of an electromagnet for my GCSE assessed practial. I set up the experiment with an iron c-core on a set of scales, and a electromagnet above, in theory, I should be able to see the weight of the c-core go down as it gets lifted off...

Right I'm doing a piece of work that needs a simple question answering. If you had two parallel electromagnets, between them a metal sheet that is being constantly vibrated with the electromagnets being used to dampen these vibrations, can you treat them as two current-carrying wires and use...

What kind of Magnetic flux do you think we could harness with a scheme like this Lightning Powered Electromagnet.

Hi all, I need to create a very large magnetic field say 1Tesla (10000 Gauss). But I can not afford to build large electromagnets like the MRI machine. However, I have two permanent magnets that will create a static field of 5000 Gauss. My question is: can I superimpose magnetic fields...

Ok, so the wire used in an electromagnet will likely have its resistance affected by a temp change on a PTC and thus require a higher voltage to maintain power, simple enough. But will an electromagnet also suffer temp coefficients for induction and coercivity and have a currie temp too?

Hi, I have been given a lab in physics. I need to create a electromagnet. The power source is a D battery, and I am given 8 nails and 3 meters of wire. I was thinking the best way to construct it would be to cut the heads off the nails and make the most solid core I can. I do not have to use all...

if you create an electromagnet and move it up and down, wouldn't that be creating electromagnetic waves? if it is, wouldn't it be possible to create x-ray, light, and radio waves by moving it at the correct speed? thinking this over i get the feeling this is not true. with this new feeling in...

build two electromagnets, stack one on top of the other so that when they receive current they will repel each other. how far can you separate them? how much current will it take for maximum separation ? what difference does it make if they each way one gram or ten tons?