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Question
Establish the relation that heat produced in a metallic conductor due to the flow of current is V2t/R joules, where V is the potential difference across the ends of the conductor, R its resistance and t is the time in second for which current flows.
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Solution
From the relation Q = Vit joule
Applying Ohm's law, V = iR
or i = V/R
Substituting the value of i, we get
Q = `"V" . "V"/"R" "t" = ("V"^2"t")/"R"` joule.
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