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> Water from a metal vessel, maintained at a potential of 3 V, falls in spherical drops of 2mm in diameter through a small hole into a thin-walled isolated metal sphere of diameter 8cm placed in air until the sphere is completely filled with water. Ignoring the thickness of the metal, calculate the final potential of the sphere and its electrical energy.
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I could find out the final potential as 4800V. That was easy. But how do I find out electrical energy? Any help or hint would be appreciated.