1. The problem statement, all variables and given/known data The earth has a vertical electric field at the surface, pointing down, that averages 117 N/C. This field is maintained by various atmospheric processes, including lightning. What is the excess charge on the surface of the earth? 2. Relevant equations E=ke*Q/r^2 Q=Er^2/ke 3. The attempt at a solution I attempted to plug in E = 117, r= radius of the earch, and ke= 8.99*10^9 into the equation to find Q, but this answer was wrong. Any ideas, thanks.