1. Safety and Overload Protection:

* Live wire carries current: The live wire is the one carrying the electrical current from the power source to the device.

* Fuse breaks the circuit: A fuse is a safety device designed to interrupt the flow of current if it exceeds a predetermined limit. This prevents overheating and potential fires.

* Neutral wire is ground reference: The neutral wire acts as a return path for the current and is connected to the earth ground. It is not meant to carry the main current flow.

2. Preventing Electrical Shock:

* Live wire is dangerous: A live wire carries a potentially lethal voltage. Contacting a live wire can result in severe electric shock.

* Neutral wire is safer: The neutral wire is generally at a much lower voltage and is considered safer to touch.

* Fuse protects the live wire: By connecting the fuse to the live wire, you ensure that the circuit will break if there's an overload or short circuit, preventing dangerous voltage from reaching the device and potentially causing harm.

3. Proper Circuit Operation:

* Fuse acts as a "gatekeeper": The fuse acts as a safety barrier between the power source and the device.

* Preventing damage to devices: If a device malfunctions or draws excessive current, the fuse will blow, preventing damage to the device and the electrical system.

* Maintaining the neutral wire's role: Keeping the neutral wire disconnected from the fuse ensures it remains a safe return path for the current and maintains the proper function of the electrical system.

In summary: Connecting the live wire to the fuse ensures that the circuit is protected from overloads and short circuits, preventing electrical shocks and damage to devices. Connecting the neutral wire to the fuse would be unsafe and could lead to malfunctions and potential hazards.