Question

The direction $\left(\theta \right)$ of $\overrightarrow{E}$ at the point P due to uniformly charged finite rod will be

• A. at an angle ${30}^o$ from the x-axis
• B. ${45}^o$ from x-axis
• C. ${60}^o$ from x-axis
• D. none of these

Answer 1

The correct option is B ${45}^o$ from x-axis

Sum of the angles in the triangle $={180}^0$, then

3rd angle will be $={180}^0-{120}^0={60}^0$

now, $\theta$ will be ${60}^0-{15}^0=\left({45}^0\right)$ because it cuts by point $P$ with in uniformly changed finises rod.