JJ Thompson

The Plum-Pudding Model


  • JJ Thompson
  • Born on December 18th, 1856
  • Died on August 30th, 1940

The "Plum-Pudding Model"

The "pudding" is the positive material (pink) and the "plums" are the electrons.


The electrons were discovered by work done with cathode rays, showing that they had momentum. It was known that for an object to have momentum it has to have mass, so it was assumed they had a stream of particles, called electrons