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Question
A uranium reactor develops thermal energy at a rate of 300 MW. Calculate the amount of 235U being consumed every second. Average released per fission is 200 MeV.
Solution
Given:
Rate of development of thermal energy = 300 MW
Average energy released per fission = 200 MeV
Let N be the number of atoms disintegrating per second.
Then, the total energy emitted per second will be
`N xx 200 xx 10^6 xx 1.6 xx 10^-19` = Power
`N xx 200 xx 10^6 xx 1.6 xx 10^-19 = 300 xx 10^6` atoms
⇒ `N = 3/(2 xx 1.6) xx 10^19 = 3/3.2 xx 10^19` atoms
6.023 × 1023 atoms = 238 gm of U235
`3/3.2 xx 10^19` atoms will present in `(238 xx 3 xx 10^19)/(6 xx 10^23 xx 3.2) = 3.7` mg
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