Question

Find out the value of resistance R in Figure :

• A. $100\Omega$
• B. $200\Omega$
• C. $50\Omega$
• D. $150\Omega$

Answer 1

Answer: (A)

$100\Omega$

Potential difference across $C$ and $D$ is $100V$.
Hence, $I_1=\frac{100}{100}=1A,V_{AC}=120-100=20V$
And $I=\frac{20}{10}=2A.Hence,I_2=2-1=1A$
$R=\frac{100}{I_2}=100\Omega$