Show that the capacitance of a spherical capacitor is `(4piepsi_(0)b^(2))/((b-a))` when the outer sphere is charged and the inner earthed.

A sperical capacitor consists of two concentric spherical conductors, held in position by suitable insulating supports. Show that the capacitance of this spherical capacitor is given by C = (4pi in_(0) r_(1) r_(2))/(r_(1) - r_(2)) , Where r_(1) and r_(2) are radill of outer and inner spheres respectively.

Capcity of a spherical capacitor is C_(1) when in sphere is charged and outer sphere is earthed and when inner sphere is earthed and outer sphere charged. Then (C_(1))/(C_(2)) is (a = radius of inner sphere b = radius of outer sphere)

The radius of spherical capacitor when capacitance is 1 muF is:

The capacitance of a spherical condenser is 1 mu F . If the spacing between the two spheres is 1mm , then the radius of the outer sphere is