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 $C$.
$(a)$ If the charge $q$ is placed at $\mathrm{C}$, the centre of a face of the cube, it is being shared equally by 2 cubes.
$\therefore$ Flux through each cube,
$\phi=\frac{\phi^{\prime}}{\epsilon_{0}}=\frac{q}{2 \epsilon_{0}}$
$(b)$ Finally, if charge $q$ is placed at $\mathrm{D}$, the midpoint of $\mathrm{B}$ and $\mathrm{C}$, it is being shared equally by 2 cubes. $\therefore$ Flux through each cube,
$\phi=\frac{\phi^{\prime}}{\epsilon_{0}}=\frac{q}{2 \epsilon_{0}}$
The electric field in a certain region is acting radially outward and is given by $E =Ar.$ A charge contained in a sphere of radius $'a'$ centred at the origin of the field, will be given by
Draw electric field lines when two positive charges are near.
Given below are two statements:
Statement $I :$ An electric dipole is placed at the centre of a hollow sphere. The flux of electric field through the sphere is zero but the electric field is not zero anywhere in the sphere.
Statement $II :$ If $R$ is the radius of a solid metallic sphere and $Q$ be the total charge on it. The electric field at any point on the spherical surface of radius $r ( < R )$ is zero but the electric flux passing through this closed spherical surface of radius $r$ is not zero.
In the light of the above statements, choose the correct answer from the options given below:
A cone of base radius $R$ and height $h$ is located in a uniform electric field $\vec E$ parallel to its base. The electric flux entering the cone is
The figure shows some of the electric field lines corresponding to an electric field. The figure suggests