Amount of Plutonium used in "Trinity" Hi, 1. The problem statement, all variables and given/known data I am asked to find the amount of Plutonium used in the 1945 experiment, first by estimating the energy released based on dimensional analysis and a photo, then using E=mc^2 and the fact that merely 0.1% of the rest mass was released during the fission. 2. Relevant equations 3. The attempt at a solution I first arrived at 1.0023*10^14 Joules (which is pretty close to the official results (8.78*10^13 Joules), then the mass would have to be 1000*E/(c^2). 1000 due to the 0.1% actually released. Which yielded 1.113 kg, but that's way off! The correct answer has to be around 6 kg. What am I doing wrong?