In the given figure of meter bridge experiment, the balancing length $AC$ corresponding to null deflection of the galvanometer is $40\,cm$. The balancing length, if the radius of the wire $AB$ is doubled, will be $....cm$
A$2$
B$40$
C$4$
D$400$
JEE MAIN 2022, Medium
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B$40$
b Independent of area in case of uniform wire.
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