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(C) Let $\rho$ be the resistivity of the material.The resistance $R$ of a conductor is given by $R = \rho \frac{L}{A}$,where $L$ is the length of the

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$C-C$

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(C) Let $ho$ be the resistivity of the material.The resistance $R$ of a conductor is given by $R = ho \frac{L}{A}$,where $L$ is the length of the conductor in the direction of current flow and $A$ is the cross-sectional area perpendicular to the current flow.$1$. For contact $A-A$ (Top and bottom faces):The length $L = x$ and the area $A = 2x 	imes 4x = 8x^2$.$R_{AA} = ho \frac{x}{8x^2} = \frac{ho}{8x}$.$2$. For contact $B-B$ (Left and right faces):The length $L = 2x$ and the area $A = x 	imes 4x = 4x^2$.$R_{BB} = ho \frac{2x}{4x^2} = \frac{ho}{2x} = \frac{4ho}{8x}$.$3$. For contact $C-C$ (Front and rear faces):The length $L = 4x$ and the area $A = x 	imes 2x = 2x^2$.$R_{CC} = ho \frac{4x}{2x^2} = \frac{2ho}{x} = \frac{16ho}{8x}$.Comparing the resistances,$R_{CC} > R_{BB} > R_{AA}$.Thus,the maximum electrical resistance is obtained for contact $C-C$.

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