ketjureaktioon
Ketjureaktioon, often translated as chain reaction, is a process in which a single event triggers a sequence of similar events. In nuclear physics, a chain reaction occurs when a neutron strikes a fissile atom, causing it to split and release more neutrons. These neutrons then go on to strike other fissile atoms, leading to a self-sustaining process. This phenomenon is the basis for nuclear power generation and nuclear weapons. The rate of a chain reaction can be controlled by adjusting the number of neutrons available to cause further fissions. This is achieved through the use of control rods made of neutron-absorbing materials. If the rate of fission is too low, the reaction will die out. If it is too high, it can lead to an uncontrolled release of energy. In other contexts, the term chain reaction can refer to any sequence of events where each event causes the next. For example, a domino effect is a type of chain reaction. A social or economic chain reaction might involve one event triggering a series of responses that have wider and wider impacts. The concept highlights the interconnectedness of events and how a single trigger can have significant propagating effects.