In an electromagnet, which of the two really becomes a magnet : the piece of iron or the coil of wire ?

Answer

To answer the question, "In an electromagnet, which of the two really becomes a magnet: the piece of iron or the coil of wire?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Components**:
- An electromagnet consists of a coil of wire (usually copper) and a piece of iron. The coil is connected to a power source (like a battery).

2. **Current Flow**:
- When the circuit is closed (the switch is turned on), electric current flows through the coil of wire.

3. **Magnetic Field Generation**:
- The flow of electric current through the coil generates a magnetic field around the coil. This is a fundamental principle of electromagnetism.

4. **Effect on the Iron**:
- The piece of iron, when placed within the magnetic field created by the coil, becomes magnetized. This means that the iron starts to exhibit magnetic properties.

5. **Magnetization of Iron**:
- As the current flows, the iron piece aligns its internal magnetic domains in the direction of the magnetic field, thus becoming a magnet itself.

6. **Observation**:
- If you bring a magnetic object (like a paper clip) near the iron piece, it will stick to the iron. This indicates that the iron has become magnetized.

7. **Conclusion**:
- Therefore, in an electromagnet, it is the piece of iron that really becomes a magnet when the current flows through the coil of wire.

### Final Answer:
The piece of iron becomes the magnet in an electromagnet.

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