AU235 nuclear reactor generates energy at a rate of 3.70×107J∕s. Each fission liberates 185MeV useful energy. If the reactor has to operate for 144×104s, then, the mass of the fuel needed is (Assume Avogadro's number =6×1023mol−1,1eV=1.6×10−19J)
In 1s, energy generated is 3.7×107J In 144×104s, energy generated is =3.7×107×144×104J Also energy released in one fission is =185meV =185×106×1.6×10−19J Number of fission =
3.7×107×144×104
185×106×1.6×10−19
=1.8×1024 of U235 atoms. Mass contained in 1.8×1024 atoms of U235 is =