A spherical balloon of radius R charged uniformly on its surface with surface density `sigma`. Find work done against electric forces in expanding it upto radius 2R.

A sperical ballon od radius R charged uniformly on its surface with surface density sigma . Find work done against electric forces in expanding it upto radius 2R.

A flat disc of radius R charged uniformly on its surface at a surface charge density sigma . About its central axis of rotation it rotates at an angular speed omega . Find the magnetic moment of disc due to rotation of charges.

A spherical shell of radius R_(1) with uniform charge q is expanded to a radius R_(2) . Find the work performed by the electric forces in this process.

A sperical shell of radius R with uniform charge q is expanded to a radius 2R. Find the work perfomed by the electric forces and external agent against electric forces in this process.

A spherical shell is uniformly charged with the surface density sigma . Using the energy conservation law, find the magnitude of the electric force acting on a unit area of the shell.

A uniform disc of radius R is charged with a uniform surface charge density sigma . Find the electric potential due to the charges on the disc at a point on its edge. [(sigmaR)/(piin_(0))]

Consider a thin spherical shell of radius R consisting of uniform surface charge density sigma . The electric field at a point of distance x from its centre and outside the shell is

A spherical shell of radius r with a uniform charge q has point charge q_(0) at its centre. Find the work performed by the electric forces during the shell expansion slowly from radius R to 2R. Also find out work done by external agent against electric forces.

A spherical shell of radius R_(1) with a uniform charge q has a point charge q_0 at its center. Find the work performed by the electric forces during the shell expansion from radius R_(1) to radius R_(2) .