7.19 understand that a chain reaction can be set up if the neutrons produced by one fission strike other U-235 nuclei

7.19 understand that a chain reaction can be set up if the neutrons produced by one fission strike other U-235 nuclei

When a U-325 splits, it gives out three neutrons. This three neutrons again hit other uranium nucleus and gives out nine neutrons. These nine neutrons hits other nuclei and keep on continuing fission reacted. This type of reaction is called chain reaction.