To what potential we must charge an insulate sphere of radius 14 cm, so that the surface charge density is equal to `2 muC m^(-2)` ?

Answer

31680 V

Explanation

Here `r = 14 cm = 14xx10^(-2) m`,
`sigma = 2 muC m^(-2) = 2xx10^(-6) Cm^(-2)`
`:. V = (1)/(4pi in_(0)) (q)/(r ) = (1)/(4pi in_(0)) (4pi r^(2) sigma)/(r ) = (4pi r sigma)/(4pi in_(0))`
`= 9xx10^(9)xx4xx (22)/(7) xx14xx10^(-2)xx2xx10^(-6)`
= 31680 V