Question

In figure, the value of R is

• A. $10\Omega$
• B. $18\Omega$
• C. $24\Omega$
• D. $12\Omega$

Answer 1

The correct option is D $12\Omega$

By KCL,

$\therefore \frac{V_p-40}{1}+\frac{V_P-100}{14}+\frac{V_p}{2}=0$

$22V_p=660$

$\therefore V_p=30V$

Potential difference between node x and y is 60 V
By taking KCL at node y

$-I-5+\frac{40-30}{1}=0$

$\therefore I=5A$

$\therefore R=\frac{60}{5}=12\Omega$