Electromagnets involve the interaction of magnetic fields and electric currents, where an electric current flowing through a coil creates a magnetic field that behaves similarly to that of a bar magnet. This phenomenon is based on the principles of electromagnetism.
Electromagnets demonstrate the interaction of magnetic fields and electric currents. An electromagnet works because an electric current produces a magnetic field; this principle is an aspect of electromagnetism. The magnetic field generated by an electric current in a coil can be visualized using iron filings, as they align with the magnetic field just as they would with a bar magnet, indicating the presence of the field around the coil. This magnetic field around the coil can attract or repel other magnets and can even induce magnetism in ferromagnetic materials when they come in close proximity.
For example, when a current flows through a wire, it creates a circular magnetic field around the wire. By coiling the wire, the magnetic field lines add together, creating a stronger magnetic field in the center of the coil. The strength of this magnetic field can be controlled by changing the amount of electric current flowing through the coil.
The correct answer to the question is d. magnetic fields and electric currents, as the electric current produces a magnetic field which interacts with magnetic materials like iron filings, compass needles, or other magnets.