Radiation may also occur naturally in the water we drink or the soils in our backyard. It even exists in food, building materials, and in our own human bodies. Radiation is used for scientific purposes, medical reasons, and the U.S. Navy uses radiation to power submarines through the water. Here's a summary of how it works. Matter is composed of very, very small particles called atoms .
Radiation comes from atoms that are in the process of changing.
The atom is the smallest unit that shows the chemical behavior characteristics of an element . The center of each atom has a nucleus that contains protons and neutrons. Protons are positively charged particles. Neutrons, which have no electrical charge, hold the protons together. Electrons are negatively charged particles.