In a household electric circuit,different appliances are connected in parallel to one another. Give two reasons for this. An electrician puts a fuse of rating $5 \, A$ in that part of a domestic electrical circuit in which an electrical heater of rating $1.5 \, kW, 220 \, V$ is operating. What is likely to happen in this case and why? What change,if any,needs to be made?

(D) Reasons for parallel connection:
$(i)$ Each appliance receives the same potential difference (voltage) as the supply source.
$(ii)$ If one appliance fails or is switched off,the others continue to operate independently.
$(b)$ Calculation:
Given: Fuse rating $= 5 \, A$,Power $(P) = 1.5 \, kW = 1500 \, W$,Voltage $(V) = 220 \, V$.
Using the formula $I = \frac{P}{V}$:
$I = \frac{1500}{220} \approx 6.82 \, A$.
Since the current required by the heater $(6.82 \, A)$ is greater than the fuse rating $(5 \, A)$,the fuse will melt (blow off) and the circuit will break.
$(c)$ Required change:
$A$ fuse with a higher rating,typically $10 \, A$,should be installed to accommodate the current drawn by the heater.