1. The problem statement, all variables and given/known data Two point charges are situated at A and B a distance of 35cm apart in a vacuum. The charge A is a positive charge of 16 μC and the field strength at X, a distance of 12 cm from A, is zero. Calculate: (i) The field strength at X due to the charge at A. (I found this to be 9.9 x 10^6 NC^-1. Just in case this is relevant to the next question.) (ii) The charge at B. 2. Relevant equations Permittivity of free space ε0 = 8.9 x 10^-12 F m^-1 F = Q.q / 4πεd^2 3. The attempt at a solution It seems like I don't have enough information but here's an attempt anyway F = (16 x 10^-6) / 4π(8.9 x 10^-12)(0.35)^2 = 1.2 x 10^6 The answer is 58.8 NC so im way off.