It can be strengthened by adding a MAGNETIC METAL CORE, such as a rod of soft iron : The soft iron core &quot;concentrates&quot; the magnetic field, making a strong electromagnet Electromagnets such as this can be made quite easily by wrapping turns of wire around a bolt or nail.
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It The soft iron core &quot It the magnetic field a strong electromagnet Electromagnets such as this
by adding concentrates can be strengthened making can be made quite easily
a MAGNETIC METAL CORE
a strong electromagnet Electromagnets such as this can be made quite easily by wrapping turns of wire around a bolt or nail