Question
Assertion : Through the same current flows through the line wires and the filament of the bulb but heat produced in the filament is much higher then that in line wires.
Reason : The filament of bulbs is made of a material of high resistance and high melting point.

Answer

(a) As filament of bulb and line wire are in series, hence current through both is same. Now, because $H=\frac{i^2 R t}{4.2}$ and resistance of the filament of the bulb is much higher than that of line wires, hence heat produced in the filament is much higher than that in line wires.

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