A point charge Q is placed at the origin . Find the electrostatic energy stored outside the sphere of radius R centred at the origin.

Explanation

Charge `= Q ` radius of sphere `= R `
Capacitance of the sphere ` C = 4pie eplison_0 R`
So, Energy `= 1 / 2 Cv^(2) `
`= 1 / 2 xx 4 pie eplison _0 R xx Q^(2) / (4 pie eplison_0 R)^(2) `
`= Q^(2) / 8 pie eplison_0 R `