[" A point charge qis brought from inflity so that heat developed in the shell is neoligitioj and is "],[" placed at the contre of external agent."],[qquad (([6],[9]))]

A point charge q is brought slowly from infinity and is placed at the centre of a conducting neutral spherical shell of inner radius a and outer radius b, then find work done by external agent :

A point charge q is brought slowly from infinity and is placed at the centre of a conducting neutral spherical shell of inner radius a and outer radius b, then find work done by external agent :

A point charge of 9.6 muC is placed at a point A. Point B is at a distance of 10 cm from A. (i) Calculate electric potential at point B due to charge at A. (ii) If a point charge of 3 nC is brought from infinity to the point B, then calculate work done by the external agent in this process assuming motion of charge to be slow.

There is a ball of radius r having uniformly distributed volume charge Q on it and there is a spherical shell of radius r having uniformly distributed surface charge Q on it. The two spheres are far apart. (a) A point charge q is moved slowly from the centre of the shell (through a small hole in it.) to the centre of the ball. Find work done by the external agent in the process. (b) The two spheres are brought closer so that their centers are separated by 4r. Now calculate the amount of work needed in slowly moving a point charge q from the centre of the shell to the centre of the ball. Assume that charge on one ball does not alter the charge distribution of the other. Does your answers in (a) and (b) differ? Why?

(a) Depict the equipotential surfaces for a system of two identical positive point charges placed a distance 'd' apart. (ii) Deduce the expression for the potential energy of a system of two point charges q_1 and q_2 brought from infinity of the points vecr_1 and vecr_2 respectively in the presence of external electric field vecE .

Consider an initially neutral hollow conducting spherical shell with inner radius r and outer radius 2r. A point charge +Q is now placed inside the shell at a distance r/2 from the centre. The shell is then grounded by connecting the outer surface to the earth. P is an external point at a distance 2r from the point charge +Q on the line passing through the centre and the point charge +Q as shown in the figure. The magnitude of the force on a test charge +q placed at P will be

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.