Consider the nuclear fission reaction ${ }_0^1 n+{ }_{92}^{235} U \longrightarrow{ }_{56}^{144} Ba+{ }_{36}^{89} Kr+3{ }_0^1 n$. Assuming all the kinetic energy is carried away by the fast neutrons only and total binding energies of ${ }_{92}^{235} U, { }_{56}^{144} Ba$ and ${ }_{36}^{89} Kr$ to be $1800 \ MeV, 1200 \ MeV$ and $780 \ MeV$ respectively,the average kinetic energy carried by each fast neutron is (in $MeV$):

Energy generation in stars is mainly due to

The binding energies per nucleon for a deuteron $(_{1}H^{2})$ and an $\alpha$-particle $(_{2}He^{4})$ are $x_1$ and $x_2$ respectively. What will be the energy $Q$ released in the reaction $_{1}H^{2} + _{1}H^{2} \to _{2}He^{4} + Q$?

An atomic power nuclear reactor can deliver $300\ MW$. The energy released due to fission of each nucleus of uranium atom $^{238}U$ is $170\ MeV$. The number of uranium atoms fissioned per hour will be:

The energy released when $\frac{7}{17.13} \text{ kg}$ of $^7_3\text{Li}$ is converted into $^4_2\text{He}$ by proton bombardment is $\alpha \times 10^{32} \text{ eV}$. The value of $\alpha$ is . . . . . . . (Nearest integer) (Mass of $^7_3\text{Li} = 7.0183 \text{ u}$,mass of $^4_2\text{He} = 4.004 \text{ u}$,mass of proton $= 1.008 \text{ u}$,$1 \text{ u} = 931 \text{ MeV/c}^2$,and Avogadro number $N_A = 6.0 \times 10^{23} \text{ mol}^{-1}$)

What is used as a moderator in a nuclear reactor?