Physics for IGCSE & O level - Magnets And Currents (Section 3 - No. 30)
What is an electromagnet?
A magnet that produces a magnetic field when an electric current flows through it.
A magnet that is always magnetic.
A magnet made of only iron.
A magnet that repels other magnets.
คำอธิบาย
An electromagnet produces a magnetic field when current flows.