How did rutherford discovery change thompson's theory

Rutherford overturned Thomson's model in 1911 with his well-known gold foil experiment, in which he demonstrated that the atom has a tiny, high- mass nucleus. In his experiment, Rutherford observed that many alpha particles were deflected at small angles while others were reflected back to the alpha source.

Explanation:

radioactive decay occurs in unstable atomic nuclei – that is, ones that don't have enough binding energy to hold

the nucleus together due to an excess of either protons or neutrons.