Explain what happens if a device that draws 8A is used with a 5A fuse and why household circuits are wired in parallel instead of series?

When a device drawing $8 \, \text{A}$ is connected to a circuit protected by a fuse rated at $5 \, \text{A}$, the current flowing through the fuse ($8 \, \text{A}$) exceeds its maximum safe rating ($5 \, \text{A}$). This excessive current causes the fuse wire to overheat and melt, breaking the circuit. This action protects the device and the wiring from damage due to overcurrent.

Household circuits are wired in parallel for several key reasons:

• Independent operation: Each appliance receives the full supply voltage and can be switched on or off independently without affecting other appliances.
• Consistent voltage: All appliances operate at their designed voltage, ensuring they function correctly. In a series circuit, the voltage would be divided among the components.
• Fault tolerance: If one appliance fails or a bulb blows, the rest of the circuit remains operational. In a series circuit, a single break would disable the entire circuit.