Question

A flat, square surface with sides of length L is described by the equations. $x=L,0\le y\le L,0\le z\le L$
The electric flux through the square due to a positive point charge q located at the origin($x=0,y=0,z=0$) is

• A. $\frac{q}{4{\epsilon }_o}$
• B. $\frac{q}{6{\epsilon }_o}$
• C. $\frac{q}{24{\epsilon }_o}$
• D. $\frac{q}{48{\epsilon }_o}$

Answer 1

The correct option is B $\frac{q}{6{\epsilon }_o}$

This can be done by assuming the cube having x,y,z direction.

$\varphi$(Flux through symmetric cube)$=\frac{q}{{\epsilon }_0}$

Cube has six faces,So flux through one face $=\frac{q}{6{\epsilon }_0}$