There are two conducting spheres of radius a and b `(b gt a)` carrying equal and opposite charges. They are placed at a separation d (`gt gt gt ` a and b). The capacitance of system is

Two identical long metal wires having radius a are held parallel to each other at a separation d (gt gt a) . Calculate the capacitance of the system per unit length.

A system of three charges are placed as shown in the figure : If D gt gt d , the potential energy of the system is :

Two spherical conductors A and B of radii a and b ( b gt a ) are placed concentrically in air. A is given charged +Q while B is earthed. Then the equivalent capacitance of the system is

Two spherical conductors A and B of radii a and b ( b gt a ) are placed concentrically in air. A is given charged +Q while B is earthed. Then the equivalent capacitance of the system is

Two spherical conductors A and B of radii a and b ( b gt a ) are placed concentrically in air. A is given charged +Q while B is earthed. Then the equivalent capacitance of the system is

Two conducting sphere of radii a and b are placed at separation d. It is given that d gt gt a and d gt gt b so that charge distribution on both the sphere remains spherically symmetric. Assume that a charge + q is given to the sphere of radius a and -q is given to the sphere of radius b. (i) Write the electrostatic energy (U) of the system and calculate the capacitance of the system using the expression of U. (ii) Prove that the capacitance of the system is given by (1)/(C)=((1)/(4 pi in_(0)a)+(1)/(4 pi in_(0)b))"if" d rarr infty

Two hollow concentric non-conducting spheres of radius the a and b (a gt b) contain charges Q_(a) and Q_(b) respectively. Prove that potential difference between the two spheres is independent of charge on outer sphere. If outer sphere is given an extra charge, is there any change in potential difference ?

Two hollow concentric non-conducting spheres of radius the a and b (a gt b) contain charges Q_(a) and Q_(b) respectively. Prove that potential difference between the two spheres is independent of charge on outer sphere. If outer sphere is given an extra charge, is there any change in potential difference ?

Two similar conducting balls having charges + q and - q are placed at a separation d from each other in air. The radius of each ball is r and the separation between their centres is d (d gt gt r ). Calculate the capacitance of the two ball system