Question

For the given semi-infinite rod of uniformly distributed line charge, find the net electric field at point $\text{P}$.

• A. $3.4\times {10}^5\text{N/C}$
• B. $4.4\times {10}^5\text{N/C}$
• C. $5.4\times {10}^5\text{N/C}$
• D. $6.4\times {10}^5\text{N/C}$

Answer 1

The correct option is D $6.4\times {10}^5\text{N/C}$

Given:
$r=1\text{m};\lambda =50\mu \text{C/m}=50\times {10}^{-6}\text{C/m}$

We know that, the net electric field at point $\text{P}$ due to semi-infinte rod is given by

$E_{net}=E_P=\frac{\sqrt{2}k\lambda }{r}$

$\Rightarrow E_P=\frac{\sqrt{2}\times 9\times {10}^9\times 50\times {10}^{-6}}{1}$

$\Rightarrow E_P=6.4\times {10}^5\text{N/C}$

Hence, option $\left(d\right)$ is correct.