Why earthing is necessary ?

Explanation

### Step-by-Step Solution:

1. **Definition of Earthing**:
- Earthing is the process of connecting the electrical system to the ground. This provides a safe path for electric current to flow into the earth in case of a fault.

2. **Prevention of Electric Shock**:
- One of the primary reasons for earthing is to prevent electric shocks. If there is a fault in the electrical system, such as a short circuit, the excess current can flow through the earthing system instead of through a person who might touch the appliance.

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