<P> The main advantage of an electromagnet over a permanent magnet is that the magnetic field can be quickly changed by controlling the amount of electric current in the winding . However , unlike a permanent magnet that needs no power , an electromagnet requires a continuous supply of current to maintain the magnetic field . </P>
<P> The main advantage of an electromagnet over a permanent magnet is that the magnetic field can be quickly changed by controlling the amount of electric current in the winding . However , unlike a permanent magnet that needs no power , an electromagnet requires a continuous supply of current to maintain the magnetic field . </P>
what advantage does an electromagnet have over a permanent magnet
what advantage does an electromagnet have over a permanent magnet
the magnetic field can be quickly changed by controlling the amount of electric current in the winding
the magnetic field can be quickly changed by controlling the amount of electric current in the winding