Introduction to J.J.Thomson atomic theory:-
Thomson discovered the electron in the year 1897. His work put forward a new theory, that atom was made up of small particles.Thus he discovered the electrons. He proved his theory using the cathode ray tube.
Scientists had already done many experiments to find the structure of the atom. They passed an electric current through a vacuum tube. They saw a light glowing inside the tube. It travelled in a straight line. They could not explain the phenomenon. Thomson did more experiments on the cathode tube. He placed two electric plates on its path. One was positively charged. The other was negatively charged. The glowing light bent towards the positively charged plate.and found that the glowing materials bent towards the positively charged plate. He found out that the glowing light were smaller particles. They were smaller than the atom. Thus Thomson found the particle called electron. Thus J.J.Thomson's atomic theory was found.