Q. The potential difference $V_{ A }-V_{ B }$ between points $A$ and $B$ for the circuit segment shown in figure-3.350 at the given instant is :

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A

$12 V$

B

$-12 V$

C

$6 V$

D

$-6 V$

Solution:

Writing equation of potential drop from terminal $A$ to $B$ gives
$V_{ A }-6-3 \times 2+\frac{9}{1}-3 \times 3=V_{ B }$
$V_{ A }-V_{ B }=12\, V$

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