$A$ spherical rubber balloon carries a charge $q$ uniformly distributed over its surface. As the balloon is inflated,the total electric flux coming out of the surface:

The black shapes in the figure below are closed surfaces. The electric field lines are shown by dashed arrows. For which case,the net flux through the surfaces is non-zero?

$A$ few electric field lines for a system of two charges $Q_1$ and $Q_2$ fixed at two different points on the $x$-axis are shown in the figure. These lines suggest that:
$(A)$ $|Q_1| > |Q_2|$
$(B)$ $|Q_1| < |Q_2|$
$(C)$ at a finite distance to the left of $Q_1$ the electric field is zero
$(D)$ at a finite distance to the right of $Q_2$ the electric field is zero

Which of the following is a correct statement?

$A$ point charge of $2.0 \; \mu C$ is at the centre of a cubic Gaussian surface $9.0 \; cm$ on edge. What is the net electric flux through the surface?

$A$ charge $q$ is placed at the center of a cubical box of side $a$ with the top open. The flux of the electric field through one of the five closed surfaces of the cubical box is: