The main source of solar energy is

The binding energies of nuclei $X$ and $Y$ are $E_1$ and $E_2$ respectively. Two atoms of $X$ fuse to give one atom of $Y$ and an energy $Q$ is released. Then:

The binding energy per nucleon in deuterium and helium nuclei are $1.1 \, MeV$ and $7.0 \, MeV,$ respectively. When two deuterium nuclei fuse to form a helium nucleus,the energy released in the fusion is ........... $MeV$.

If the energy released per fission of a ${ }_{92}^{235} U$ nucleus is $200 \text{ MeV}$, the energy released in the fission of $0.1 \text{ kg}$ of ${ }_{92}^{235} U$ in kilowatt-hour is:

Which one of the following nuclear reactions is a source of energy in the sun?

Nuclear fission and fusion can be explained on the basis of