What charge would be required to electrfy a sphere of radius 25 cm, so as to get a surface charge density of `(3)/(pi)"Cm"^(-2)` ?

Explanation

Here, `r=25cm=0.25m,sigma=(3)/(pi)"Cm"^(-2)`
As, `sigma=(q)/(4pir^(2))`
`:." "q=4pir^(2)sigma=4pixx(0.25)^(2)xx(3)/(pi)=0.75C`