All the faces of a cube are parallel to the coordinate axes. Therefore, the number of field lines entering the cube is equal to the number of field lines piercing out of the cube. As a result, net flux through the cube is zero.
A line charge of length \( \frac{a}{2} \) is kept at the center of an edge BC of a cube ABCDEFGH having edge length \( a \). If the density of the line is \( \lambda C \) per unit length, then the total electric flux through all the faces of the cube will be : (Take \( \varepsilon_0 \) as the free space permittivity)
A metallic sphere of radius \( R \) carrying a charge \( q \) is kept at a certain distance from another metallic sphere of radius \( R_4 \) carrying a charge \( Q \). What is the electric flux at any point inside the metallic sphere of radius \( R \) due to the sphere of radius \( R_4 \)? 

“One of these days you’re going to talk yourself into a load of trouble,” her father said aggressively. What do you learn about Sophie’s father from these lines? (Going Places)
Write a letter to the editor of a local newspaper expressing your concerns about the increasing “Pollution levels in your city”. You are an environmentalist, Radha/Rakesh, 46, Peak Colony, Haranagar. You may use the following cues along with your own ideas: 