Question

A nuclear **** is required to deliver 1 MeV of heat energy. How many fission events must be required to attain this power level. If this **** is designed with a nuclear fuel consisting of U235 to run a reactor at this power level for one year then calculate the amount of fuel needed. It is given that energy released per fission event is 200 MeV.

Answer 1

Energy required by nuclear ***** = 1 MW = 106 Js–1

Energy released by fission = 200 MeV

= 200×1.6×10–13 = 3.2×10–11 J

No. of fission required per second

Number of fission required per year by 1 MW energy release

= 3.125 × 1016 × 365 × 24 × 60 × 60 = 9.9 × 1023

Hence amount of uranium fuel needed is

= 386.46 g