Consider a $72\, cm$ long wire $AB$ as shown in the figure. The galvanometer jockey is placed at $P$ on $A B$ at a distance $x cm$ from $A$. The galvanometer shows zero deflection.
The value of $x,$ to the nearest integer, is ..... $cm$
A$40$
B$64$
C$48$
D$24$
JEE MAIN 2021, Medium
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C$48$
c In $B$ alanced conditions
$\frac{12}{6}=\frac{x}{72-x}$
$x=48\, cm$
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