$A$ hydrogen bomb is based on which of the following phenomena?

What is the energy released by the fission of $1 \, g$ of $U^{235}$?

The minimum frequency of a photon required to break a particle of mass $15.348 \ amu$ into $4 \ \alpha$ particles is . . . . . . $kHz$.
[Mass of $He$ nucleus = $4.002 \ amu$, $1 \ amu = 1.66 \times 10^{-27} \ kg$, $h = 6.6 \times 10^{-34} \ J \cdot s$ and $c = 3 \times 10^8 \ m/s$]

In a material medium,when a positron meets an electron,both particles annihilate,leading to the emission of two gamma-ray photons. This process forms the basis of an important diagnostic procedure called:

In an atomic reactor and an atomic bomb,the multiplication factor $(r)$ per fission is respectively:

State the principle of an atomic bomb and identify the nuclear process that occurs within it.