The electric field intensity on the surface of a charged solid sphere of radius '$$r$$' and volume charge dentiy '$$\rho$$' is given by ($$\epsilon_0=$$ permittivity of free space)
Let A, B and C be the three points in a uniform electric field $$\text { ( } \overrightarrow{\mathrm{E}})$$ as shown. The electric potential is
Two positive ions, each carrying a charge 'q' are separated by a distance 'd'. If 'F' is the force of repulsion between the ions, the number of electrons from each ion will be ($$\varepsilon$$ = charge on $$\varepsilon_k$$ = permittivity of free space)
Three charges $$-\mathrm{q}, \mathrm{Q}$$ and $$-\mathrm{q}$$ are placed at equal distances on a straight line. If the total potential energy of the system of three charges is zero then the ratio $$\frac{Q}{q}$$ is