Question

The given four terminal network is a part of larger circuit. The points A, B, C are at the same potential. The potential difference between any one of A, B or C and point D is $40V$. The potential difference between A & O is

• A. 10 V
• B. 15 V
• C. 18 V
• D. 20 V

Answer 1

Answer: (A)

10 V

$\Rightarrow V_{AD}=40$
$\Rightarrow R_{eff}=\frac{R}{3}+R=\frac{4R}{3}$
$\Rightarrow I\times R_{eff}=40$
$I\times \frac{4R}{3}=40$
$\Rightarrow IR=30$
$V_{AO}=\frac{I}{3}\times R$
$=\frac{30}{3}=10V$