He entered without telling his tutor, who on learning of his candidacy told him he was wasting his time - `that is just like you Thomson, never asking my advice.' He was elected. The following year Thomson submitted a dissertation for the Fellowship Election at Trinity. The Senior Wrangler that year was Joseph Larmor, who became famous later for his contributions to theoretical physics. Thomson took the Tripos in 1880 and was placed second. In those days the Wranglers (undergraduates with First Class in the Mathematics Tripos) were placed in order of merit, and there was great competition to come top of the list. He therefore gave up engineering and in 1876 came to Trinity College, Cambridge to read Mathematics. It was originally intended that he should be an engineer, and, at the age of fourteen, he was sent to Owens College - later Manchester University - until there was a vacancy for an apprentice at the engineering firm selected.Īfter two years his father died, and his mother could not afford the large premium required for the apprenticeship. His father was a bookseller and publisher. The same way, it can be written for all the elements present in the periodic table.Joseph John Thomson was born on Decemin Cheetham, a suburb of Manchester. The electronic configuration for oxygen can be written as 2, 6, for nitrogen, it will be 2, 5, and for aluminum, it will be 2, 8, 3. The energy shell or level just after this is capable of having a maximum of eight numbers of electrons.
The shells of level one can have two electrons at the maximum. The innermost shell will be having the lowest of all the available energy. The electrons are placed in the energy shells or levels around the nucleus. The configuration mentioned describes how the electron particles are placed around the atom’s nucleus. The arrangement of the electrons can be interpreted by the electronic configuration. The radioactivity transformation and the stability of an atom are dictated by a nuclear structure, while the chemical features or properties of an atom are decided by an electronic arrangement. The count of protons being equal to the count of electrons results in an element’s neutral atom. The neutrons and the protons particles are approximately 1836 times of the electron particles in terms of mass. The only negatively charged particle named electrons have a mass of around 0.00055 amu. The neutron particles are neutral (electrically), and their mass is around 1.00876 amu. The protons have a positive charge, and their mass is around 1.0072 amu. The neutrons and the protons are collectively termed as the nucleons. The nucleus has two particles named neutrons and protons. The atom also has electrons present near the nucleus, and the electrons are actually orbiting the nucleus. Atoms have a nucleus that is present at the center of the atom. The smallest constituent of the atom present in a substance or a matter is the electron.
#Jj thomson cathode ray experiment led to the discovery of free
Other than finding the electrons, Thompson could also conclude that the mass-to-the charge ratio of the cathode rays was free of the properties of the gas or metal electrodes, which lead him to consider electrons as one of the basic constituents of all the atoms. These negatively charged particles were named as the electrons. As it is known that the opposite charges always attract each other while the like charges repel one another, Thompson was able to estimate that the particles involved here had some negative charge. These particles got emitted from the cathode with the negative charge and were repelled by an electric field’s negative terminal. Thomson was also able to estimate the mass-to-the charge ratio of the particles involved just by estimating the deflection extents of the rays of the cathode in the electric or magnetic fields having different strengths.
This demonstration was capable enough to bring up the fact that the cathode rays have some charged particles. He showed that the cathode rays can be bent or deflected by the electric or magnetic fields present nearby. The deflection of the rays of the cathode was demonstrated by Thompson. J.J Thomson stated and proved that the most basic constituent of the matter was not atoms but atoms too had some constituents and those constituents could be some particles inside the atoms.