Describe the principle of an atom bomb. What is meant by critical mass ? What is the criticalmass of `._(92)U^(235)` ?

Explanation

The working principle of atom bomb is based on uncrontrolled nuclear fission chain reaction. Where two or more pieces of fissionable materials such as uranium `-235` or plutonium `-239(` each with sub`-` critical mass `)` are brought together by means of explosive then a single piece of fissionable material is formed. The mass of this single piece exceeds the critical mass and therefore nuclear fission starts and an uncontrolled chain of nuclear reaction is set up within a very short time. In this uncontrolled nuclear chain reaction, a tremendously large amount of heat energy is liberated which causes destruction of lives, buildings, and almost everything that may come in its way.
Critical mass `:` In order for explosion to occur in a nuclear reactor, the mass of the fuel has to be greater than some minimum value called the critical mass. The critical mass of `._(92)U^(235)` i s 1 to `100kg`.