View full lesson: http://ed.ted.com/lessons/radioactivity-expect-the-unexpected-steve-weatherall
Neutrons don't change into protons. Except, sometimes, they do. Radioactivity is the process under which the nucleus can change spontaneously from one element to another. Steve Weatherall suggests that we acknowledge both the usefulness and danger inherent in harvesting radioactivity.
Talk by Steve Weatherall, animation by Eugene Uymatiao.