Two cylindrical rods, of different material, are joined as shown. The rods have same cross section (A) and their electrical resistivities are rho_(1) and rho_(2). When a current I is passed through the rods, a charge (Q) gets piled up at the junction boundary. Assuming the current density to be uniform throughout the cross section, calculate Q.

Two cylindrical rods, of different material, are joined as shown. The

1.	Two cylindrical rods, of different material, are joined as shown. The rods have same cross section (A) and their electrical resistivities are rho_(1) and rho_(2). When a current I is passed through the rods, a charge (Q) gets piled up at the junction boundary. Assuming the current density to be uniform throughout the cross section, calculate Q.
Answer» ANSWER :`Q=(rho_(2)-rho_(1))in_(0)I` Q is negative if `rho_(a) gt rho_(2)`]

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