Question

For the resistance network shown in the figure, choose the correct option(s).

• A. The current through PQ is zero
  
• B. $I_1=3A$
• C. The potential at $S$ is less than that at $Q$
• D. $I_2=2A$

Answer 1

Answer: (A), (B), (C), (D)

The correct options are
A The current through PQ is zero

B $I_1=3A$
C The potential at $S$ is less than that at $Q$
D $I_2=2A$

By symmetry, we can conclude that 1 $\Omega$ resistances will not receive any current, so circuit reduces to
$I_1=\frac{12}{\frac{6\times 12}{6+12}}=3A$

$I_2$ is $\frac{2}{3}$ of $I_1.$

$I_2$ = 2 $A$