If a charge $q$ is placed at the centre of the flat surface of a closed hemispherical non-conducting surface,what is the total electric flux passing through the flat surface?

Two surfaces $S_1$ and $S_2$ are shown in the figure. The electric flux associated with $S_1$ is $\phi_1$ and with $S_2$ is $\phi_2$. Which of the following is correct?

What is the electric flux for Gaussian surface $A$ that encloses the charged particles in free space? [Given: $q_1 = -14 \text{ nC}, q_2 = 78.85 \text{ nC}, q_3 = -56 \text{ nC}$]

Draw the electric field lines for a positive point charge.

Which among the following has dimensions of charge?

An infinitely long thin non-conducting wire is parallel to the $z$-axis and carries a uniform line charge density $\lambda$. It pierces a thin non-conducting spherical shell of radius $R$ in such a way that the arc $PQ$ subtends an angle $120^{\circ}$ at the centre $O$ of the spherical shell,as shown in the figure. The permittivity of free space is $\epsilon_0$. Which of the following statements is (are) true?
$(A)$ The electric flux through the shell is $\sqrt{3} R \lambda / \epsilon_0$
$(B)$ The $z$-component of the electric field is zero at all the points on the surface of the shell
$(C)$ The electric flux through the shell is $\sqrt{2} R \lambda / \epsilon_0$
$(D)$ The electric field is normal to the surface of the shell at all points