Question

In the figure, the potential difference between $a$ and$b$ is:

• A. $0V$
• B. $15V$
• C. $10V$
• D. $5V$

Answer 1

The correct option is C

$10V$

Step 1: Given information

$V=30V$

$R_1=10K\Omega ,R_2=10K\Omega and{R}_3=10K\Omega$

A diode is an electrical component that allows current to flow in only one direction.

A diode is represented in circuit diagrams by a triangle with a line through one vertex. Because the diode is at forwarding bias, it will behave like a simple wire.

Since the diode is in forwarding bias so it will behave like a wire.

Therefore, the circuit can be drawn as below.

The total resistance is given as $R+R=2R$ if two identical resistors are linked in series.

Now, $10\text{k}\Omega \text{and 5 k}\Omega$ are connected in series the net resistance is

$\therefore 10+5=15\text{\hspace{0.17em} k}\Omega$

Step 3: Draw a circuit diagram and calculate the potential difference

$\begin{array}{c}\text{Current =\hspace{0.17em}}\frac{Voltage}{Resis\tan c{e}_{Net}}\\ =\frac{30}{15\times {10}^3}\\ =2\times {10}^{-3}\\ =2\text{mA}\end{array}$

$\begin{array}{c}\text{Now,}Voltag{e}_A-Voltag{e}_B=i\times Resis\tan c{e}_{AB}\\ =2\times {10}^{-3}\times 5\times {10}^3\\ =10\times {10}^{-3+3}\\ =10\text{\hspace{0.17em}V}\end{array}$

Hence, the correct option is (C).