J. J Thomson(18 Dec 1856- 30 Aug 1940)
Joseph John Thomson was born in 1856 in Cheetham Hill, Manchester England. His mother, Emma Swindells, came from a local textile family. His father, Joseph James Thomson, ran an antiquarian bookshop founded by a great grandfather from Scotland. He had a brother, Frederick Vernon Thomson who is 2 years younger than him.
His early education was in a small private school. He demonstrated a great talent and interest in Science. In 1810 he was admitted to Owens College. His parents planned to enroll him as an apprentice engineer to Sharp-Stewart and co. but these plans were cut short when his father died in 1873. In 1884 he became a Cavendish Professor of Physics. One of his students was Ernest Rutherford. In 1890, he married Rose Elisabeth Paget, daughter of Sir George Edward Pager. He fathered one son named George Paget Thomson and one daughter Joan Paget Thomson.
The plum pudding model of J.J Thomson, discovered the electron in 1897 and was proposed in 1904 even before the atomic nucleus was discovered. In the model, the atom was composed of electrons (which Thomson called corpuscles) surrounded by a soup of positive charge to balance the electrons' negative charges. * REMEMBER: NEGATIVELY CHARGED PLUMS SURROUNDED BY POSITIVE-CHARGED PUDDING
With this model, Thomson abandoned his earlier Nebular Atom hypothesis in which the atom was composed of immaterial vorticies.
In this model, the electrons were free to rotate within the blob or cloud of positive substances. These orbits were stabilized in the model by the fact that when an electron moved father from the center of the cloud, it felt a larger net positive inward force because there was more material of opposite charge inside the orbit.
The 1904 model was disproved by the 1909 gold foil experiment which was interpreted by Ernest Rutherford in 1911 to imply a very small nucleus of the atom containing a very high positive charge.
"It is the charm of physics that there are no hard and fast boundaries, that each discovery is not a terminus but an avenue leading to country as yet unexplored, and that however long the science may exist, there will still be an abundance of unsolved problems…"
-J.J Thomson
Submitted By Group 5:
Mia San Juan
Cierra Mortega
Alex Vergara
Elma Tejada
Jhoanne Sanchez
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