Please see the attached file.
We have a disk of radius R and uniform surface charge density A shown below.
a) What is the potential with respect to infinity at a distance Z above the center of this disk?
b) If A equals 9 pC/m^2 and R = 4m what is the potential at the point Z = 3m in V
c) What is the electric field at Z=3m in V/m given the parameters in part B
It investigates the electric field and potential of a disk with uniform surface charge. The solutin is detailed and has a rating of '5/5'.