If a point charge be rotated in a circle of radius r around a charge q. what will be the work done?

A charge of +1 C is placed at the centre of a spherical shell of radius 10 cm. what will be the work done in moving a charge of +1muC on its surface through a distance of 5 cm?

A small sphere of radius r_1 and charge q_1 is enclosed by a spherical shell of radius r_2 and charge q_2 . Show that if q_1 is positive, charge will necessarily flow from the sphere to the shell (when the two are connected by a wire) no matter what the charge q_2 on the shell is.

In an electric field the work done in bringing a 2 coulomb charge from infinity to a point a is 10 joules and in bringing the same charge to some another point B is 20 joule find the potential difference between two points A and B what would be the work done if the same charge is brought directly from A to B.

Two identical point charges of charge Q are kept at a distance r from each other. A third point charge is placed on the line joining the above two charges, such that all the three charges are in equilibrium. Calculate the magnitude and location of the thrid charge.

What whould be the work done, if a point charge .+q. is taken from a point A to a point B on the circumference of a circle drawn with another point charge +q at the centre?

What would be the work done if a point charge + q is taken from a point A to the point on the circumference of a circle with another point charge +q at the centre?

If a point charge +q is taken first from A to C and then from C to B of a circle drawn with another point charge +q as centre as shown in the figure, then along which path more than will be done.

If the same charge of Q coulomb as in part above is given to a spherical conductor of the same radius R, what will be the energy of the system?