A metel rod of the length 10cm and a rectangular cross-section of 1 cm xx `1//2` cm is connected to a battery across opposite faces. The resistance will beA. maximum when the battery is connected across `1cmxx(1)/(2)cm` facesB. maximum when the battery is connected across `10cmxx1cm` facesC. maximum when the battery is connected across `10cmxx(1)/2 cm` faces.D. Same irrespective of the three faces.

A metel rod of the length 10cm and a rectangular cross-section of 1 cm

1.	A metel rod of the length 10cm and a rectangular cross-section of 1 cm xx `1//2` cm is connected to a battery across opposite faces. The resistance will beA. maximum when the battery is connected across `1cmxx(1)/(2)cm` facesB. maximum when the battery is connected across `10cmxx1cm` facesC. maximum when the battery is connected across `10cmxx(1)/2 cm` faces.D. Same irrespective of the three faces.
Answer» Correct Answer - A The resistance of wire is given by `R=rho(l)/(A)` For greater value of R, l must be higher and A should be lower and it is possible only when the battery is connected across `1cmxx((1)/(2))cm` (area of cross-section A).

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