AP Physics 2 "Little Boy" Nuclear Activity (13 points) Background: The United States developed the world's first nuclear weapons during World War II. On 6 August 1945, the first atomic weapon ever used in warfare was deployed over Hiroshima, Japan. This bomb, codenamed "Little Boy," was a detonation with a uranium core. On 9 August 1945, a second atomic bomb was deployed over Nagasaki, Japan. This bomb, codenamed "Fat Man," was a detonation with a plutonium core. In this activity, you will analyze Little Boy's nuclear reaction. Little Boy contained 64 kg of enriched uranium, and when detonated, produced 63 TJ (terajoules) of energy. Enriched uranium is U-235, instead of the more common U-238. When this rare isotope absorbs an additional neutron, it becomes unstable and fissions. The nuclear reaction is: "U+ on - " Ba + Kr + 3on + energy The reactants and products are listed below in unified atomic mass units (u). 235U = 235.043924 u on = 1.008664 u 144Ba = 143.922953 u as Kr = 88.917631 u Note: A unified atomic mass unit is 1/12th of the mass of a carbon-12 atom. Fe 30 He 7 6 Lis Average binding energy per nucleon (MeV) A H3 He N 1 H 0 30 60 90 120 150 180 210 240 270 Number of nucleons in nucleusQuestions: 1. (5) Calculate the number of unified atomic mass units (u) converted to energy during a U-236 fission reaction. 2. (2) Calculate the energy released by each fission of a U-236 atom in MeV. 3. (2) Calculate the amount of mass (kg) converted to energy during Little Man's detonation. 4. (4) Explain why energy is released during a U-236 (U-235 plus a neutron) fission detonation. Use the concept of binding energy in your explanation with a diagram