JEE Mains · Physics · STD 12 - Electric charges and fields
- JEE Mains 2025
- Easy
- MCQ
An infinitely long wire has uniform linear charge density \(\lambda=2 \mathrm{nC} / \mathrm{m}\). The net flux through a Gaussian cube of side length \(\sqrt{3} \mathrm{~cm}\), if the wire passes through any two corners of the cube, that are maximally displaced from each other, would be \(\mathrm{xNm}^2 \mathrm{C}^{-1}\), where x is :
[Neglect any edge effects and use \(\frac{1}{4 \pi \varepsilon_0}=9 \times 10^9\) SI units]
Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(2.16 \pi\)
Step-by-step Solution
Detailed explanation

\(\begin{aligned} & \phi=\frac{\mathrm{q}_{\mathrm{enc}}}{\varepsilon_0}=\frac{\lambda \cdot \sqrt{3} \mathrm{a}}{\varepsilon_0} \\ & =2 \times 10^{-9} \times \sqrt{3} \times \sqrt{3} \times 10^{-2} \times 36 \pi \times 10^9 \mathrm{Nm}^2 \mathrm{C}^{-1} \\ & =2.16 \pi \mathrm{Nm}^2 \mathrm{C}^{-1}\end{aligned}\)
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