Question

Find the potential difference $V_P-V_Q$ between points $\text{P}$ and $\text{Q}$ as shown below.

• A. $0\text{V}$
  
• B. $1\text{V}$
  
• C. $-4\text{V}$
  
• D. $2\text{V}$
  

Answer 1

The correct option is A $0\text{V}$


Using potential-drop method, we can write the potentials of different points as shown in figure.


Using $\text{KCL:}$

$1[0-(V+4\left)\right]+2[0-(V-4\left)\right]+2[0-(V+2\left)\right]=0$

$\Rightarrow -V-4-2V+8-2V-4=0$

$\Rightarrow V=0\text{V}$

$\Rightarrow V_P-V_Q=V-0=0-0=0\text{V}$

Hence, option $\left(D\right)$ is the correct answer.