Two large plane parallel conducting plates are kept 10 cm apart as shown in figure. The potential difference between them is $V$. The potential difference between the points A and B (shown in the figure) is :

• A

  $\frac{1}{4} \mathrm{~V}$
• Correct answer
  B

  $\frac{2}{5} \mathrm{~V}$
• C

  $\frac{3}{4} \mathrm{~V}$
• D

  1 V

Solution

$\begin{aligned} & \text { Using } \Delta V=E(\Delta d) \\ & V=E(10) \\ & V_{A B}=E \cdot 4=\frac{V}{10} \times 4=\frac{2 V}{5}\end{aligned}$

Hence, the correct answer is option: 'B'.