Q-1:- If the electric field near the earth's surface be 300 Vm directed downwards, what is the surface density of the charge on the earth's surface........... Q-2:- Two metallic spheres of radii Ri and R2 have equal surface densities of charge. The ratio of electric fields on their surfaces is......... Q-3:- A charge "Q" is uniformly distributed over a long rod (A-B) of length "L". The electric potential at the point "p" lying at a distance "L" from its one end "A" is........... Q-4:- What potential difference must be applied to produce an electric field that can accelerate an electron to one-tenth of the speed of light? (Given the mass of electron is 9.110-27 g and the charge of e or q is 1.610-19 C and speed of light C-3.0105 km/s) Q-5:- The electrostatic force between the two point charges is 0.5 N. If one of the charge become 2 times and the distance between them has been decreased by 1/3, therefore the new force Fl will become........ Q-6: What will be the acceleration due Coulomb's Force on a proton, if the acceleration of electron is 2.51022 m/s Q-7: The potential difference (p.d.) of the order of 7.25 eV (electron-Volt) will be equal to energy................ ........ Q-8: What will be the electric potential, if potential energy / work done is 81.0 J to bring a charge of 9.0 C at a certain distance from infinity.............. Q-9:- Caleulate the value of electric field (E) for a surface, if the coefficient of surface charge density is 16 10-22 N/Cm........... Q-10:- What will the value of electric force if two charges of 5.0 C and 9.0 nC are at distance of 1A......