According to Joule's law,if the potential dif | vedclass

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(D) The power dissipated as heat in a conductor is given by $P = \frac{V^2}{R}$.We know that the resistance $R$ of a conductor is given by $R = \frac{

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$\frac{1}{\rho}$

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(D) The power dissipated as heat in a conductor is given by $P = \frac{V^2}{R}$.We know that the resistance $R$ of a conductor is given by $R = \frac{\rho l}{A}$,where $\rho$ is the specific resistance (resistivity),$l$ is the length,and $A$ is the cross-sectional area.Substituting the expression for $R$ into the power formula,we get $P = \frac{V^2}{(\rho l / A)} = \frac{A V^2}{\rho l}$.Given that the potential difference $V$,length $l$,and cross-sectional area $A$ are constant,the term $\frac{A V^2}{l}$ is a constant.Therefore,$P \propto \frac{1}{\rho}$.Thus,the heat produced is directly proportional to $\frac{1}{\rho}$.

According to Joule's law,if the potential difference across a conductor having a material of specific resistance remains constant,then the heat produced in the conductor is directly proportional to

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