Question

In what way household appliances should be connected and why?

Answer 1

They are connected in parallel. The reason for the parallel connection is that it results in each appliance operating at the same voltage (i.e., approximately 120V for line-neutral connected appliances, and 240V for appliances that are connected line-line) along the entire circuit. Each appliance/load draws from the source (the circuit supplied by the circuit breaker in the electrical panel) the current it needs to operate, based on its impedance, according to Ohm’s law: I = V/Z, where V is the circuit voltage and Z is the associated load impedance, and I is the current that the circuit will supply to that particular load. When the appliances/loads are connected in parallel, you can independently connect or disconnect any appliance/load from the circuit (and/or turn its associated power switch on and off), and the rest of the appliances/loads on the same circuit continue to operate normally/ The only time you get into trouble is when you connect too many appliances/loads to a single circuit, that collectively draw more current than what the circuit (and its associated circuit breaker) can safely supply. When this happens, the circuit breaker supplying and protecting the circuit trips and opens up the circuit, and all of the appliances/loads on that circuit turn off, until you unplug an adequate amount of load (i.e., number of appliances) that the circuit can safely supply. You identify and disconnect the offending loads, reset the (tripped) circuit breaker that supplies that circuit, make a mental note not to connect that many appliances/loads to that circuit again, and you’re good to go.

Answer 2

Household appliances should be connected in parallel because if short circuiting occurs in one appliance the others work efficiently.
Whereas the main fuse should be connected in series because if there is overloading, the fuse will melt preventing the damage that could be caused to your property