Electromagnets are made by passing ____ through them.

Answer

**Step-by-Step Solution:**

1. **Understanding Electromagnets**: Electromagnets are a type of magnet where the magnetic field is produced by an electric current.

2. **Components of an Electromagnet**: An electromagnet typically consists of a core made of iron and insulated wire wound around it.

3. **Current Flow**: When electric current flows through the wire, it creates a magnetic field around the wire and magnetizes the iron core.

4. **Behavior of Electromagnets**: The key characteristic of an electromagnet is that it only behaves like a magnet when electric current is flowing through the wire. Once the current stops, the magnetic field disappears, and it no longer behaves like a magnet.

5. **Conclusion**: Therefore, the correct answer to the question is that electromagnets are made by passing **electric current** through them.

**Final Answer**: Electromagnets are made by passing **electric current** through them.

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