Question

Equivalent resistance of the given infinite circuit is

• A. 4$\Omega$
• B. 2$\Omega$
• C. Infinity
• D. Greater than 4$\Omega$ but less than 6$\Omega$

Answer 1

Answer: (D)

$\frac{R\times2}{R+2}+4=R$
$2R +4R+8=R^{2}+2R$
$R^{2}-4R-8=0$
$R=\frac{4\pm\sqrt{16+32}}{2}$
$=\frac{4+\sqrt{48}}{2} =5.46\Omega$