In an $\alpha -$ decay,the kinetic energy of the $\alpha -$ particle is $48 \ MeV$ and the $Q$ value of the reaction is $50 \ MeV$. The mass number of the mother nucleus is (assume that the daughter nucleus is in the ground state).

The binding energy per nucleon of deuteron $({ }_{1} H^{2})$ and the helium atom $({ }_{2} He^{4})$ are $1.1 \ MeV$ and $7 \ MeV$ respectively. If two deuteron nuclei fuse to form a single helium nucleus,then the energy released is: (in $MeV$)

When Uranium is bombarded with neutrons,it undergoes fission. The fission reaction can be written as ${}_{92}U^{235} + {}_0n^1 \to {}_{56}Ba^{141} + {}_{36}Kr^{92} + 3x + Q$,where three particles named $x$ are produced and energy $Q$ is released. What is the name of the particle $x$?

Assertion : It is not possible to use ${}^{35}Cl$ as the fuel for fusion energy.
Reason : The binding energy of ${}^{35}Cl$ is too small.

In a nuclear reactor,heavy nuclei are not used as moderators because:

In a nuclear reactor,boron rods are used as ...... .