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The resistance will be least in a wire w...

The resistance will be least in a wire with length, cross-section area respectively,

A

L/2, 2A

B

2L, A

C

L, A

D

L, 2A

Text Solution

Verified by Experts

The correct Answer is:
A
Resistance `R = rho l ..A` or `R prop l //A`.
`therefore " " R_(a)prop(L)/(4A), R_(b)prop (2L)/(A), R_(c )prop(L)/(A)`.
Thus, resistance is least in a wire of length L/2 and area of cross-section is 2A.
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