Question

what is nuclear power reactor

Answer 1

nuclear reactor, formerly known as an atomic pile, is a device used to initiate and control a sustained nuclear chain reaction. Nuclear reactors are used at nuclear power plants for electricity generation and in propulsion of ships.

Answer 2

The most common types of reactor are the Pressurised Water Reactor and the Boiling Water Reactor. For more details look up Wikipedia entries for these titles, you will find diagrams that help to understand better than words alone.it varies based on the design. Some are very small, but they are classified. One that I worked on, a BWR, had a reactor pressure vessel that was 20 feet in diameter, 80 feet long, and 6 inches thick. The active fuel region, however, was only 12 feet long.