A sample of magnetised iron is heated to about` 900^@C` and then cooled down in a region free of magnetic field. Will it retain its magnetism?

Explanation

To determine whether a sample of magnetized iron retains its magnetism after being heated to about 900°C and then cooled in a region free of magnetic fields, we can follow these steps:

### Step 1: Understand the Concept of Curie Temperature
The Curie temperature is the temperature at which a magnetic material loses its magnetic properties. For iron, this temperature is approximately 750°C.

### Step 2: Analyze the Heating Process
When the magnetized iron is heated to 900°C, it exceeds its Curie temperature (750°C). At this temperature, the thermal energy is sufficient to disrupt the alignment of magnetic domains within the iron, causing it to lose its magnetism.

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