State and explain Joule’s law of heating.
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Joule's law of heating states that heat produced in joule when a current of I amphere flows in a wire of resistance R ohms for time t secounds is
Given by $H = I^2Rt$
Thus the heat produced in a wire is directly proportional to:
  1. Square of current.
  2. Resistance of wire.
  3. Time for which current is passed.
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