Question

Three infinitely long charge sheets are placed as shown in figure. The electric field at point P is

• A. $\frac{2\sigma}{\varepsilon_{0}} \hat{k}$
• B. $- \frac{2\sigma}{\varepsilon_{0}} \hat{k}$
• C. $\frac{4\sigma}{\varepsilon_{0}} \hat{k}$
• D. $-\frac{4\sigma}{\varepsilon_{0}} \hat{k}$

Answer 1

Answer: (B)

The electric field due to an infinite plane sheet of charge is independent of distance of point from the sheet. Applying the principle of superposition of electric field, the total electric field at P due to various plane sheets of charge will be
$\vec{E}_{p}=\frac{\sigma}{2\varepsilon _{0} }\left(-\hat{k}\right)+\frac{2 \sigma }{2\varepsilon_{0}}\left(-\hat{k}\right)+\frac{\sigma }{2\varepsilon_{0}}\left(-\hat{k}\right)=-\frac{2\sigma }{\varepsilon_{0}}\hat{k}$