What is the condition for electric flux through an area to be maximum?

What is the unit of electric flux?

Define electric flux.

The electric flux through the surface

What is the physical meaning of electric flux?

S_1 and S_2 are two hollow concentric spheres encloing charges Q and 2 Q respectively as shown in Fig What is the ratio of electric flux through S_1 and S_2 ?

What is the net flux of the uniform electric field through a cube of side 20 cm oriented so that its faces are parallel to the coordinate planes?