Understanding Electromagnets
Electromagnets are a type of magnet in which the magnetic field is produced by an electric current. They can attract certain materials, but not all substances respond to this force.
Why Iron is Attracted by Electromagnets
- Ferromagnetic Material: Iron is classified as a ferromagnetic material. This means it has the ability to be magnetized and respond strongly to magnetic fields.
- Magnetic Domains: In iron, small regions called magnetic domains align with the external magnetic field when subjected to an electromagnet. This alignment enhances the overall magnetic effect, allowing iron to be attracted to the electromagnet.
- Strong Attraction: The attraction between an electromagnet and iron is significant because iron can easily become magnetized and retains some magnetism even when the current is turned off.
Why Other Materials Are Not Attracted
- Wood: Wood is a non-magnetic material. It does not contain magnetic properties and therefore does not respond to magnetic fields.
- Plastic: Similar to wood, plastic is also non-magnetic. It does not contain ferromagnetic materials and shows no attraction to an electromagnet.
- Rubber: Rubber, like plastic and wood, lacks magnetic properties and does not interact with magnetic fields.
Conclusion
In summary, the correct answer to the question is option 'B', Iron, as it is the only material among the choices that is attracted by an electromagnet due to its ferromagnetic properties.