1. Home
  2. Education
  3. Chemistry

Sir Joseph John (J. J.) Thomson

By , About.com Guide

Sir Joseph John (J. J.) Thomson

Sir Joseph John (J. J.) Thomson

Born:

December 18, 1856, Cheetham Hill, near Manchester, England

Died:

August 30, 1940, Cambridge, Cambridgeshire, England

Claim to Fame:

Discovered the electron.

Notable Awards:

Nobel Prize in Physics (1906)
Knighted (1908)

Summary:

Many scientists studied the electric discharge of a cathode ray tube. It was Thomson's interpretation that was important. He took the deflection of the rays by the magnets and charged plates as evidence of "bodies much smaller than atoms". Thomson calculated these bodies had a large charge to mass ratio and he estimated the value of the charge itself. In 1904, Thomson proposed a model of the atom as a sphere of positive matter with electrons positioned based on electrostatic forces.

Explore Chemistry

About.com Special Features

A Smarter Future

Tips that will help finance your education, excel in the classroom, and advance your career. More >

How to Ace the GRE

Being well prepared is the first step; here are more essential suggestions. More >

  1. Home
  2. Education
  3. Chemistry
  4. Chemistry Disciplines
  5. History of Chemistry
  6. Sir Joseph John (J. J.) Thomson (1856–1940)>

©2009 About.com, a part of The New York Times Company.

All rights reserved.