Because the incoming electrically charged particle induces current in the coils of the electromagnet.
A permanent magnet does not have to deal with that - even if there is current it doesn't affect the magnetism in a permanent way.
Think about an electric solenoid: A stationary electromagnet does not consume power, a moving one does as it acts on the external magnets.
Because the incoming electrically charged particle induces current in the coils of the electromagnet.
A permanent magnet does not have to deal with that - even if there is current it doesn't affect the magnetism in a permanent way.
Think about an electric solenoid: A stationary electromagnet does not consume power, a moving one does as it acts on the external magnets.