Question

In the given circuit, the potential difference between $A$ and $B$ is

• A. 0
• B. 5 volt
• C. 10 volt
• D. 15 volt

Answer 1

Answer: (C)

Here $p-n$ junction is forward biased. If $p-n$ junction is ideal, its resistance is zero. The effective resistance across $A$ and $B$
$=\frac{10\times10}{10+10}=5\,K\Omega$
Current in the circuit
$I=\frac{30}{\left(10+5\right)\times10^{3}}=\frac{2}{10^{3}}$
$\therefore $ Current in each arm $=\frac{I}{2}=\frac{1}{10^{3}}A.$
$=\frac{1}{10^{3}}\times10\times10^{3}=10\,V$