Mammoth Memory

The difference between an electromagnet and a solenoid

An electromagnet is an electrically induced magnet.

As the name implies it is a core of magnetic material (such as iron) surrounded by a coil of wire through which an electric current is passed to magnetise the core.

An electromagnet looks like the following:

Electromagnet

A solenoid is a cylindrical coil of wire acting as a magnet when carrying an electric current. A solenoid is the same as an electromagnet but without a core of material that can be magnetised i.e. iron (which is magnetically soft).

Solenoid

NOTE: A solenoid still produces a magnetic field but not as strong as an electromagnet of the same size. Infact the magnetic field with the iron core in is over 1000 times stronger (yes - one thousand times).

 

To remember what a solenoid is, just use the mnemonic:

Solenoid = Stolen and Void

Just imagine that the core of an electromagnet has its core stolen and there is now a void.

 

Summary

An electromagnet is a coil of wire around an iron core.

A solenoid is just a cylindrical coil of wire.

 

Conclusion

Wrapping the coil around an iron core makes for a stronger magnetic field.

 

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