The coercive force for a certain material is `10^4` A/m. A magnet made out of this material is placed inside a solenoid having 1000 turns/metre. What amount of electric current is required to demagnetise the material completely?

Explanation

To solve the problem, we need to find the amount of electric current required to demagnetize a magnet made of a material with a coercive force of \(10^4\) A/m, placed inside a solenoid with 1000 turns per meter.

### Step-by-Step Solution:

1. **Identify the Given Data:**
- Coercive force (\(H_c\)) = \(10^4\) A/m
- Number of turns per meter in the solenoid (\(N\)) = 1000 turns/m

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