How much electric flux will come out through a surface $S = 10\hat j$ kept in an electrostatic field $\vec E = 2\hat i + 4\hat j + 7\hat k$………$units$

What will be the total flux through the faces of the cube as in figure with side of length $'a'$ if a charge $'q'$ is placed at ?

$(a)$ $C$ $:$ centre of a face of the cube.

$(b)$ $D$ $:$ midpoint of $B$ and $C$.

A few electric field lines for a system of two charges $Q_1$ and $Q_2$ fixed at two different points on the $\mathrm{x}$-axis are shown in the figure. These lines suggest that $Image$

$(A)$ $\left|Q_1\right|>\left|Q_2\right|$

$(B)$ $\left|Q_1\right|<\left|Q_2\right|$

$(C)$ at a finite distance to the left of $\mathrm{Q}_1$ the electric field is zero

$(D)$ at a finite distance to the right of $\mathrm{Q}_2$ the electric field is zero

How field lines depend on area or on solid angle made by area ?

Two charged thin infinite plane sheets of uniform surface charge density $\sigma_{+}$ and $\sigma_{-}$ where $\left|\sigma_{+}\right|>\left|\sigma_{-}\right|$ intersect at right angle. Which of the following best represents the electric field lines for this system