Question

In the circuit as shown in figure, if a battery is connected between points A and C of e.m.f E 18 V, then current flowing through the battery is

• A. 15 A
• B. 5 A
• C. 20 A
• D. 10 A

Answer 1

Answer: (D)

$i \frac {18\,V}{R_{AC}}$
$R_{AC} = R_{AB} +R_$
$\frac {1}{R_BC}= \frac {1}{18} +\frac {1}{9} + \frac {1}{3} + \frac {1}{6} +\frac {1}{3}$
$= \frac {1+2+8+3+6}{18}$
$R_{BC} = 1\Omega$
then
$R_{AC} =\frac {4}{5} +1 \Rightarrow \frac {9}{5}\Omega $
then, $i = \frac {18} {5} \Rightarrow {10} A$