Potential difference across $A B$ in the network shown is .........
A$0$
B$E$
C$E-\frac{l r}{2}$
D$E-2lr$
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A$0$
a (a)
$i=\frac{E}{R}$
$V_A-E+i r-E+i r=V_B$
$V_A-E+E-E+E=V_B$
$V_A=V_B$
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