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A metel rod of the length 10cm and a rec...

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 be

A

Maximum when the battery is connected across `1 cm xx 1/2 cm` faces.

B

Maximum when the battery is connected across `10 cm xx 1 cm` faces.

C

Maximum when the battery is connected across `10 cm xx 1/2 cm` faces.

D

Same irrespective of the three faces

Text Solution

Verified by Experts

The correct Answer is:
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 cm `1 cm xx (1/2) cm` (area of crosssection A)
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