Electromagnet Definition and 372 Threads

Given an electromagnet which has a drastically lower impedance than other, comparable electromagnets (same diameter, same gauge wire, same field strength), and, consequently, a much faster response time, what uses do you see this being good for? I'm looking to put together a patent...

I know you can used iron wrapped around with copper coil to create electromagnet , can it be done with steel? Or must it always be iron?

Hey I'm new here so I don't know if this is the right forum, but from what I could see this was the most relevant. Homework Statement A long solenoid with 50 turns per cm carries a current of 0.2 A. The solenoid is filled with an iron alloy. The magnetic field B inside the iron alloy...

Homework Statement Hi, I've been trying to figure this out for days. I've wrapped an insulated wire that I got at Lowe's around a large metal nail. I then connected it to a knife switch and a 9v battery (per the directions). The nail is supposed to pick up 30 paperclips. I've tried wrapping...

Hello this is my first time to post. I have an electromagnet powered by a car battery charger set at 12 volts the problem is I can't get the electromagnet to repel the neodymium magnet. I have tried switching around the positive and negative leads of the power supply and switching the side of...

I'm trying to predict the possible pull force of some electromagnets from the following equation: FPull= ( n x I ) 2 μ0\frac{A}{(2 g ) ^ 2} F : Force. n : Number of turns. I : Current. μ0 : permeability of air. A: Area in m2 g : the gap that is separating the electromagnet and the object...

Hello, I have been performing an experiment in which I am observing the lifting capacity of DC electromagnets while changing variables including current, number of turns, and length of the core. It is a fairly basic experiment as all the theoretical values can be obtained using the formula...

Recently, I made an electromagnet by winding copper wire (length: 4m) around a metal screw. The power supply was from a mobile phone charger (5V). Here's the issue: When I connected the electromagnet in series with a 10 ohms resistor, it worked fine (attracted nearby metal objects), but...

Hello, If we have an electromagnet with some lifting force, for example 10N, and make core area smaller at the ends, to concentrate the magnetic field (without saturating the core) according to the formula, for magnetic flux magnetic field density B , will be greater. For example if we...

Hi guys and gals Long story short I'm trying to make an magnetic levitator (like you can see on youtube), basically a floating metal ball, this will be part of a project I'm doing but the issue is I have absolutely no idea how to go about designing a electromagnet from scratch (which is a...

Hello! My first post at Physics Forums! Nice to meet you! In an electromagnet, where the coil windings are not touching themselves (the coil is not touching itself), is there any difference on the magnet strength created depending on whether the wire is insulated or not (bare wire)? If the...

Hi, I decided to do a little weekend project and build an electromagnet. I read online to use copper wire and wrap it around an iron core. I was wondering If I could use anything other than iron, also, I hope you guys can tell me where I can commonly find the parts necessary for this project...

Is there a reason why a wire coil inside of an iron pipe wouldn't work as an electromagnet?

Hello, I'm trying to levitate the iron core of an electromagnet at a certain postion. How can I calculate what the minimum currennt is that I need to put on the electromagnet to prevent the core from falling out at the bottom? Is there an equation to know at what position the core will be...

Hi my name is HopelesslyFaithful (HF) (forum didn't allow all chars). I am from Notebookreview and while googling for my project. I came across this site a thread that was helpful but also made more questions. I posted this on NBR so i did a direct copy paste hoping i could get some expert help...

I am trying to make a DC electro magnet coil. The Coil is wound up to the core. And works fine. But I'm not being able to find out the inductance of the coil. The Resistance of Coil R20= 490 ohms. Impedence is 523 Ohms. 110v give .21 amps. Please Help.

Hi guys, I am building an electromagnet to use mainly for its reaching properties. I want to have a large air gap. I don't care if the magnet can only lift a paper clip but I do care if it can move it from a 15 to 20 cm distance or more. I only have 1 core to work with so my choices are only...

So.. I'm a biomedical engineer, and a new technology that is arising is being able to control magnets that "swim" around the body using electromagnets oriented around the outside of the patients body. It has been said that electromagnets can't be used on the inside of the patient because they...

Could anyone help me with calculating the force between an electromagnet and a permanent magnet? Using Biot-Savart law I'm able to calculate the field strength of the electromagnet at a respective point, I can also calculate the field strength of the permanent magnet. However, the tricky part...

Hi, I need help with my electro magnet pulse with modulation PWM. I have a Velleman® IR Light Barrier Kit from Radio Shack and this kit is ment to turn on and off a 9V buzzer. But instead of soldering in the buzzer I tried to hook it up to a MOSFET transistor NTE2984 so that I could use it with...

hello everyone, I've spent countless hours and a ton of money on trying to get this work. What I am making is a electromagnet with a decent amount of strength, but mine doesn't work at ALL. I am using copper megnetic wire and have tried both 9V AND AA. I've included pictures of both my coil...

I have been looking for a better way to power my electromagnet than a bunch of AA batteries, and am now thinking of using ultracapacitors. I have a few questions. I have been looking on ebay for them, I don't know of better options, and I have seen mostly 2.7V with >1F, up to 1500F. One...

I have built a new electromagnet, my second one so far, in an attempt to make it better. I am trying to find its strength, whether that be in tesla, holding force (kg) or whatever other units there are, just so I can compare it with other magnets. What I have is a steel bolt wrapped with...

I've had some bad trouble trying to create an electromagnet, so I've come here in hopes of help. Basically, I need to create an electromagnet strong enough to lift 2kg of weight. Because I don't know much on the subject, I have attempted this by wrapping insulated copper wire about an iron...

Confused about electromagnet?? How do i calculate the magnet field for an Solenoid with an ironcore with x windings and y amps.. The same for an horseshoe magnet, where there is an air gap about 2mm.. For some reason does my calculation not make sense..

I am trying to make an electromagnet sphere shape about 6 inches OD. Is this possible?

I have created a simple electromagnet that is just an iron railroad spike with some thick insulated wire wrapped around it. This is connected to a dodgy, old motorbike battery (I'm thinking of being a decent battery...). I have looked up how you measure the strength, but I'm not sure what is...

We are going over magnetism in my Physics 2 course but we barely covered electromagnets. I was wondering what the math equation for field strength would be for an electromagnet. In other words, how is current related to field strength when you wrap a wire around a piece of metal. Also I was...

Hi to all, I'm new to the forum and forgive me if I'm not in the right place. I have a drag knife sign making cutter which uses an electromagnet to drop and raise the knife. The shaft that runs through the coil rattles/vibrates and although the machine cuts ok it drives me mad. Obviously the...

It's been many years since I studied this so I would appreciate some confirmation on the formula and its parts. The formula I was taught to calculate the Gauss of an electromagnet was: B=MNI/2R with: B = Magnetic flux in Gauss M= Magnetic permeability of core material N =...

How can you have a simple coil connected to a battery without having a short circuit in it? How do they make electromagnets that don't heat the battery? Thanks :)

hi all, i have just signed up to this site to find some assistance with the above topic. i am building an electromagnetic propagator to study the effects of varying field strengths on the germination of seeds and the rooting of cuttings. it has been many years since i last look into...

Help in designing a small yet very powerful electromagnet! I was wondering what are the major things I should concentrate in creating a strong electromagnet? What are the best materials to use? The input source I'm going to use is a 1.5V dc battery. What do you all recommend? + How can I...

Given the same voltage and current, hence electrical power, what kind of core design can maximize the "reach" of an electromagnet? For example, with the magnet above a table, axis pointing down at the table, attempting to lift a small iron washer, is there a core design that significantly...

Hello :)I was working on a project for one of my classes, and it had to do with electromagnets + magnet's B field interactions(A simple demonstration of a few laws of electromagnetism). Basically its a simple configuration like this random photo I found...

Hi, I wanted to create electromagnet around pipeline to produce 0.2 Tesla magnetic field. How can it be connected to the DC from 220 Volt.. Please help me..

Hi, I would like to know if Neodymium Magnets can be used as an electromagnetic magnet. The idea is to get a Neodymium Magnet and add DC voltage to do the Gauss Law. The college project is make a very powerful electromagnet, so I thought adding the most powerfull magnet and the some DC...

Dear all, I need realizing an electromagnet producing a magnetic field changing in direction with a given frequency (from 100 to 800kHz). Max intensity should be 400-500 Oe. I need applying this magnetic field in a small region (10x 10 mm2) and I would prefer the electromagnet not so big...

i'm making an electromagnet with a battery, some copper wire, and a iron solenoid/core. For the core I'm using is a magnetic spoon, i was just wondering, will it work? here's a picture, http://img706.imageshack.us/img706/9348/spoont.jpg , I'm not done wrapping the wire basically it's...

Help me clear up something. I know the magnetic field of an electromagnet's core is given by , where N is the number of turns of wire. Now, the resistance of the wire is given by R = ρ*λ/A, where ρ is the resistivity, and λ the length of the wire. Using Ohm's law to combine them, I get: But...

I hear a setup like the one in the pic will drain the battery in minutes, and using an AC source will mean an oscillating field and heating. So what other options do I have for a power source if I want a working homemade electromagnet?

Hey guys, is it possible to design a Bitter eletromagnet that produces 25T and is approximately 500 cm3 in size? If so, how much current would it require? Thanks in advance for your responses guys..

Hi, This is my first post, and if this is the wrong area, I apologize. I was wondering if anyone knows of a software package that will design the pole faces for a quadrupol or hexapole electromagnetic beam focusing magnet given the beam parameters and electromagnetic magnetic field strength...

i have done an investigation on an electromagnet, i set up and electromagnet by wrapping coils of a wire round an iron core, a few mm below this i had an iron plate on a set of scales. When i turned the electromagnet on the mass on the scales went down as the iron plate was being attracted to...

I am looking at electromagnets and discovered an article using an A/C version. What I am surprised by is that there is no mention of how the A/C is being used. http://www.coolmagnetman.com/magacem.htm Wouldn't someone creating this version of an electromagnet kill themselves? There's no...

There is a post on this forum stating that the insulation should be left on the wire to prevent a short circuit thus making the electromagnet ineffective. Lost the link and can't find it now. But I am finding multiple articles on the internet that are using bare wire. Ex of bare...

I want to make an electromagnet to rapidly switch polarity back and forth. I hear the core should be made of laminated iron to avoid heat losses; is this correct? Where could I get one such core from, and is there anything else I should consider?

Please find the attached picture.. My understanding : Use right hand thumb rule to find the direction of magnetic flux lines when the direction of currents are known. When I have a 'cross', the lines will be in clockwise direction while I have a 'dot', the lines will be in anticlcokwise...

I was toying with the idea of making an iron core electromagnet to retrieve a broken portion of my driveshaft from a recess in the end of the crankshaft on my boat motor. The mechanic at my work said I wouldn’t be able to do it, so I figured I would entertain the idea. The driveshaft is...

Hello all! How fast can an electromagnet get magnetised and de-magnetised, by DC-pulsing it and without having any hysteresis & retentivity effects in the coil itself? Obviously its not going to be a ferrite core coil(because of retentivity,hysteresis). How fast can a low power...