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Current Electricity — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsCurrent Electricity2 Marks
Question
Current is allowed to flow in a metallic wire at a constant potential difference. When the wire becomes hot, cold water is poured on half of its portion. By doing so, its other half portion becomes still more hot. Explain its reason.
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Answer

When cold water is poured on half the wire, the resistance of this portion decreases, and hence the current $\text{I}=\frac{\text{V}}{\text{R}}$ in whole wire increases and so the other half portion becomes still more hot.

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