An electric current flows along an insulated strip $PQ$ of a metallic conductor. The current density in the strip varies as shown in graph of figure. Which one of the following statements could explain this variation ?
Medium
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The current density at $\mathrm{P}$ is higher than at $\mathrm{Q}$ For the same current flowing through the metallic conductor $\mathrm{PQ},$ the cross sectional area at $\mathrm{P}$ is narrower than at $\mathrm{Q}$.
The resistance per unit length $\mathrm{r}$ is given by $x=\rho \frac{1}{A}$
where $\rho$ is the resistivity and $\mathrm{A}$ is the cross-sectional area of the conductor $\mathrm{PQ}$.
Thus, $\mathrm{r}$ is inversely proportional to the cross-sectional area $\mathrm{A}$ of the conductor.
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