What is the function of an earth wire? Why is it necessary to earth metallic appliances?

Explanation

### Step-by-Step Solution:

1. **Understanding the Function of an Earth Wire:**
- The primary function of an earth wire is to provide a safe path for electric current to flow into the ground in case of a fault or leakage. This helps in protecting electrical appliances from sudden damage that can occur due to excess or leakage current.

2. **Protection from Leakage Current:**
- When there is a fault in an electrical appliance, it may cause leakage current, which can lead to overheating or damage to the appliance. The earth wire ensures that this leakage current is diverted safely to the ground, preventing potential damage.

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