# Electromagnet with External Iron 'Core'

• LordBerkley

#### LordBerkley

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

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Yes. Conventionally the core concentrates field lines generated by the coil wrapped around it. The return path is through the air, so field lines extend a considerable distance from the core allowing it to attract ferromagnetic objects. In your geometry, the return path of lines from the pipe is through the center of the coil. The field falls away rapidly with distance, making it basically suitable only for sticking to a thin plate. A simliar geometry is used for permanent magnets intended to stick onto sheet metal--magnets in the base of removable car radio antennas, e.g.

1 person

## 1. What is an electromagnet with an external iron core?

An electromagnet with an external iron core is a type of magnet that uses electricity to create a magnetic field. The iron core is a ferromagnetic material that enhances the strength of the magnetic field produced by the electromagnet.

## 2. How does an electromagnet with an external iron core work?

An electric current is passed through a coil of wire, which creates a magnetic field. When the iron core is placed in the center of the coil, it becomes magnetized and strengthens the magnetic field. This allows the electromagnet to lift heavier objects or attract magnetic materials.

## 3. What are the advantages of using an electromagnet with an external iron core?

The main advantage of this type of electromagnet is its increased strength and versatility. By using an external iron core, the magnetic field can be easily controlled and adjusted by varying the amount of current flowing through the coil.

## 4. What are the applications of an electromagnet with an external iron core?

Electromagnets with external iron cores have a wide range of applications, including in industrial settings for lifting and moving heavy objects, in electric motors and generators, and in medical imaging machines.

## 5. Can an electromagnet with an external iron core be turned off?

Yes, an electromagnet with an external iron core can be turned off by stopping the flow of electric current through the coil. When the current is turned off, the iron core loses its magnetism and the magnetic field disappears.