Assertion : Current is passed through a metallic wire, heating it… - Vidyadip

Question

Assertion : Current is passed through a metallic wire, heating it red. When cold water is poured on half of its portion, then rest of the half portion become more hot.
Reason : Resistances decreases due to decrease in temperature and so current through wire increases.

✓

Answer

(a) When cold water is poured on half portion of the wire, its resistance decreases due to decrease in temperature. As a result of this total resistance of circuit decreases i.e. current through each portion of wire increases i.e. rest of the half portion becomes still more hot.

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