i am trying to solve this problem which states that J(p) = (I/pi) p^2 e^-p^2 in z direction is the current density flowing in the vicinity of insulating wire. pi = pie in standard spherical polar coordinates. J is the current density. I need to prove that the total current flowing through the wire is I. I have tried to used the idea J.dS = I where and integrate(i have taken the scale factor into consideration) but it does not yield the right result. Any suggestion on a way to move forward will be appreciated.