Consider a house in which a 200 W study lamp and a 1000 W electric iron are connected…
PHYSICS · Subjective · CBSE · Physics · Magnetic Effects of Electric Current · Magnetic Effects of Electric Current
Problem
Consider a house in which a 200 W study lamp and a 1000 W electric iron are connected in parallel to a 240 V, 50 Hz single-phase supply.
(i) Calculate the reading, in kilowatt-hours, that will be recorded by the energy meter if both appliances are used simultaneously for 2 hours.
(ii) Suddenly the neutral wire in the supply cable breaks while the live conductor remains intact. Analyse step by step what will happen to the circuit potential, the working of each appliance, and the safety of a person touching the iron at that instant.
(iii) Name TWO protective devices or practices installed in a domestic circuit that are intended to minimise the hazard described in part (ii), and explain the working principle of each.