Part of Physics (Single Science) Unit 1: Atomic and nuclear physics Most of the mass and all of the positive charge of an atom is in the nucleus. Most of an atom is empty space, (a vacuum). In 1897, ...

Photo: Niels Bohr's research notes for his new atomic theory Rutherford's find came from a very strange experience. Everyone at that time imagined the atom as a "plum pudding." That is, it was roughly ...

Physicists got their first look at the structure of the atomic nucleus. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. The Geiger-Marsden ...

Protons are tiny particles just a femtometer across, but without them, atoms wouldn't exist. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.