Question

12 resistors each of 10$\Omega$ are connected as shown in figure. The effective resistance between A and B is

• A. 120$\Omega$
• B. 8$\Omega$
• C. 12$\Omega$
• D. 10$\Omega$

Answer 1

Answer: (B)

8$\Omega$

(By symmetric rule)
$\frac{1}{R_{eff}}=\frac{3\times 2}{4\times 20}+\frac{1}{20}$
$=\frac{1}{20}\times \frac{5}{2}$

$R_{eff}=8\Omega$