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I am studying over the basic introductory concepts of magnetism, and I cannot comprehend definition of the following words below:

Electromagnets- objects that are magnetic only when electric current is flowing.

induced magnetism- magnetism that is present only when an electric current is flowing.

The only difference that I notice is the object and magnetism, yet it seems that those two words relate so much to each other.

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  • $\begingroup$ We usually talk about induced magnetism of ferromagnets that are near or in contact with permanent magnets. $\endgroup$ – CuriousOne Apr 27 '16 at 21:09
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An electromagnet is a magnet only when current is flowing through it. Materials which are used to make electromagnets have particular properties, specifically low retentivity and low coercivity. Retentivity is the property of a material which makes it retain a bit of the magnetic field once the magnetic intensity reduces to 0. While coercivity is the magnetic intensity required to erase that amount of magnetic field the material retained when the external magnetic intensity was made zero.

Permanent magenta on the other hand are usually made from materials which have a high retentivity and high coercivity. Basically a permanent magnet is made by placing a ferromagnetic material inside solenoid and applying a field. Because of the aforementioned characteristics of a permanent magnetic, it gets a net magnetisation when the external magnetic field is removed.

I'd like to suggest you to familiarise yourself with the italicised words for a better understanding of the definitions you've mentioned.

Basically both are due to current. But one (electromagnets) stops being magnetic when the external current producing the field is switched off. While the other (permanent magnets produced by magnetic induction) remains magnetic when the current stops because of a net magnetisation.

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Think of a scrapyard and the electromagnet that is hung by cables from a crane to pick up, say cars. This electromagnets needs a constant current running through it to maintain the magnetic effect.

So the electric current induces a magnetic effect in the iron base of the electromagnet. It's the physical process of induced magnetism that creates the electromagnet.

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