The total electric flux through a closed spherical surface of radius $r$ enclosing an electric dipole of dipole moment $2 a q$ is (Give $\varepsilon_0=$ permittivity of free space)
Under electrostatic conditien of a charged conductor, which among the following statements is true?
A cube of side 1 cm contains 100 molecules each having an induced dipole moment of $0.2 \times 10^{-6} \mathrm{C}-\mathrm{m}$ in an external electric field of $4 \mathrm{NC}^{-1}$. The electric susceptibility of the materials is ................ $\mathrm{~C^2N}^{-1} \mathrm{~m}^{-2}$
A capacitor of capacitance $5 \mu \mathrm{~F}$ is charged by a battery of emf 10 V . At an instant of time, the potential difference across the capacitors is 4 V and the time rate of change of potential difference across the capacitor is $0.6 \mathrm{Vs}^{-1}$. Then, the time rate at which energy is stored the capacitor at $\geq$ instant is