P=density, Q=total charge r=radial distance ; p(r)= Q/((4*pi*R))*((e^-r/R)/r^2)?

explain why the element of charge, dq, located within an infinitesimally-thin spherical shell of radius r is equal to p(r)4*pi*r^2dr, where dr is the thickness of the shell.
2 answers 2