What happens when ferromagnetic substance is heated to high temperature?

Explanation

### Step-by-Step Solution:

1. **Definition of Ferromagnetic Substances**:
- Ferromagnetic substances are materials that exhibit strong magnetic properties. They have a high degree of magnetization in the direction of an applied magnetic field. Common examples include iron, cobalt, and nickel.

2. **Effect of Heating on Ferromagnetic Substances**:
- When ferromagnetic substances are heated to high temperatures, they undergo a change in their magnetic properties.

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