The problem statement, all variables and given/known data 1, What is the electric field around the conducting sphere of radius R carrying a charge Q? 2, What is the electric potential at the surface of the sphere if the potential infinately far away is zero? 3, Hence obtain a formula for the capacitance of the sphere. 4, Assuming the Earth to be a huge conducting sphere of radius 6.4*10^4 m surrounded by air find the capacitance of the earth. The attempt at a solution I have a solution for 1 which is E=kQ/r^2. I cannot do the rest of it, although i beleive that I have to use gausses law although i quite simply dont know how to do this. Any helps or suggestions would be more that welcome. Many Thanks.