A spherical capacitor consists of two concentric spherical conductors, held in position by suitable insulating supports (Fig. 2.36). Show that the capacitance of a spherical capacitor is given by


Where r1 and r2 are the radii of outer and inner spheres, respectively.


Radius of the outer shell = r1


Radius of the inner shell = r2


Charge on the inner surface of the outer shell = Q


Charge on the outer surface of the inner shell = -Q


Potential difference between the two shells,



Where, = Absolute Permittivity of free space = 8.8510-12C2N-1m-2


Since, Capacitance,




Hence, proved.


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