The purpose of JJ Thomson's experiment was to study the properties and behavior of particles inside a vacuum, specifically the properties of the electron.
Thomson's experiment revealed that the electron has a much smaller mass compared to the atom and that it carries a negative charge.
Thomson's experiment provided evidence for the existence of subatomic particles and challenged the popular theory at the time that atoms were indivisible. This led to the development of the atomic model and further advancements in the field of physics.
Thomson's experiment showed that electrons, which were previously thought to be solely responsible for electricity, also have a role in magnetism. This helped develop our understanding of the relationship between electricity and magnetism and led to the development of electromagnetic theory.
Thomson's experiment involved passing electricity through a cathode ray tube, which was a narrow glass tube with a positively charged anode and a negatively charged cathode. He then placed a magnet near the tube and observed the deflection of the cathode rays, which helped him determine the properties of the electrons.