If you took introductory physics, you learned about the “fundamental forces.” It goes something like this: All interactions ...

The electron and proton are attracted to each other. This attraction holds the atom together ... When the plastic is moved near the desk, electrons in the desk are repelled by the negatively charged ...

As they studied atomic disintegration, they kept seeing that the atomic number (number of protons in the nucleus, equivalent to the positive charge of the atom) was less than the atomic mass ...