Gauss' Law has been fairly tough for me and I seem to be struggling to analyze situations properly and, specifically, decided on the net charge included in arbitrary symmetrical-shapes used for this law. Specifically, this one includes two spherical shells. 1. The problem statement, all variables and given/known data A point charge q1 = -5.3 μC is located at the center of a thick conducting shell of inner radius a = 2.1 cm and outer radius b = 4.2 cm, The conducting shell has a net charge of q2 = 1.1 μC. 1) What is Ex(P), the value of the x-component of the electric field at point P, located a distance 7.2 cm along the x-axis from q1? 2. Relevant equations E=Qenc/ε°=∫E (dot) dA For Spherical Symmetry - E=Qenc/4πr2εo 3. The attempt at a solution Initially, I drew a (not so) arbitrary sphere of radius 7.2cm so that P is enclosed in the surface. Based off the wording of the problem, I assumed that the total Qenclosed in this arbitrary sphere is 1.1μC. Given this, I calculated 1.1μC/4∏(.072m)2ε° which, evidently, came out to be incorrect. As I referred to earlier, it seems that I am struggling to find out what the actual enclosed charge is.