Q47 of 94 Page 442

Calculate the energy released by 1g of natural uranium assuming 200 MeV is released in each fission event and that the fissionable isotope 235U has an abundance of 0.7% by weight in natural uranium.

Given, 1g of sample contains 0.007g 235U

And 235g of 235U contains 6.023× 1023 atoms


0.007g contains × 0.007 atoms


1 atom releases 200MeV energy


So, total energy= Energy released per atom× total no. of atoms



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49

A town has a population of 1 million. The average electric power needed per person is 300W. A reactor is to be designed to supply power to this town. The efficiency with which thermal power is converted into electric power is aimed at 25%.

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(c) Assuming that uranium enriched to 3% in 235U will be used, how much uranium is needed per month (30 days)?