1 artificial permanent 2 electromagnetic3 natural
I suppose they all do; Electromagnets are probably the most useful as they can be switched on and off instantaneously. They are used in motors, loudspeakers, relays, televisions etc. artificial permanent magnets can also be found in electric motors, loudspeakers, reed switches etc. As far as i can think natural magnets don't have many applications. but they could be used to make loudspeakers, motors and to operate reed switches for sure. So in short, they all have several applications in electrical equipment. Sorry not to be of more help.
