Question

The energy released by the fission of one uranium atom is $200MeV$. The number of fission per second required to produce $6.4W$ power is _____

• A. ${10}^{11}$
• B. $2\times {10}^{11}$
• C. ${10}^{10}$
• D. $2\times {10}^{10}$

Answer 1

The correct option is B $2\times {10}^{11}$

Energy released per fission $E=200MeV=200\times {10}^6\times 1.6\times {10}^{-19}J=3.2\times {10}^{-11}J$
Total energy produced in one second $E_p=6.4J$
Number of fission per second $N=\frac{E_p}{E}=\frac{6.4}{3.2\times {10}^{-11}}=2\times {10}^{11}$
Correct option is B.