Question

Three resistances of values 2$\Omega$, 3$\Omega$ and 6$\Omega$ are to be connected to produce an effective resistance of 4$\Omega$ . This can be done by connecting

• A. 6$\Omega$ resistance in series with the parallel combination of 2$\Omega$ and 3$\Omega$
• B. 3$\Omega$resistance in series with the parallel combination of 2$\Omega$ and 6$\Omega$
• C. 2$\Omega$resistance in series with the parallel combination of 3$\Omega$ and 6$\Omega$
• D. 2$\Omega$ resistance in parallel with the parallel combination of 3$\Omega$ and 6$\Omega$

Answer 1

Answer: (C)

2$\Omega$resistance in series with the parallel combination of 3$\Omega$ and 6$\Omega$

Answer 2

Parallel combination of 3$\Omega$ and 6$\Omega$ gives effective resistance,
$R_p=\frac{3 X 6}{3+6}=\frac{18}{9}=2\Omega$This in series with
2 $\Omega$ gives net ressistance as 4 $\Omega$