10.5 Fission

Which has a larger energy yield per fission reaction, a large or small sample of pure $^{235} \text{U} ?$

Should an atomic bomb really be called nuclear bomb?

In what way is an atomic nucleus like a liquid drop?

(a) Calculate the energy released in this rare neutron-induced fission $n + ^{238} \text{U} \rightarrow ^{96} \text{S} \text{r} + ^{140} \text{X} \text{e} + 3 n$, given $m \left(^{96} \text{S} \text{r}\right) = 95.921750 \text{u}$ and $m \left(^{140} \text{X} \text{e}\right) = 139.92164$.

(b) This result is about 6 MeV greater than the result for spontaneous fission. Why?

(c) Confirm that the total number of nucleons and total charge are conserved in this reaction.

The electrical power output of a large nuclear reactor facility is 900 MW. It has a $35.0 \%$ efficiency in converting nuclear power to electrical power.

(a) What is the thermal nuclear power output in megawatts?

(b) How many $^{235} \text{U}$ nuclei fission each second, assuming the average fission produces 200 MeV?

(c) What mass of $^{235} \text{U}$ is fissioned in 1 year of full-power operation?