J.J. Thomson and the Electron

By Becca Joseph and Jenna Fiore

Full name: Joseph John Thomson Was born on December 18, 1856 in

Cheetham hill, England Died August 30,1940 in Cambridge, Uk Married to Rose Paget and had two children

General Information

Started college at the age of 14 at Owens college in Manchester

He then received a scholarship to go to Trinity College at Cambridge

At Trinity he was studying mathematics Did research at Cavendish Laboratory Was mentored by Lord Rayleigh

Thomson’s Education

• At the Cavendish Laboratory at Cambridge University, Thomson was experimenting with cathode rays• He saw currents of electricity inside Crooker

tube (was not the first to use it) • He decided that the rays were streams of

particles much smaller than atoms, they were pieces of atoms • After lots of experiments, Thomson’s

suggestion proved to be correct and the rays are electrons

Discovery of the Electron

He couldn't measure directly the mass or the electric charge of such a particle

He could measure how much the rays were bent by a magnetic field, and how much energy they carried

From this data he could calculate the ratio of the mass of a particle to its electric charge (m/e)

Finding the Mass to Electric Charge Ratio

• Electrons: very small, negatively charged particles that are fundamental parts of every atom

 

More on the Electron

• He studied cathode rays • He discovered that all matter is made up of tiny

particles smaller than atoms• He studied positively charged ions• He discovered that neon was composed of two

different kinds of atoms (isotopes)• He discovered the electron

J.J Thomson’s most important work

• Thomson discovered the electron in the year 1897.

• His work showed that the atom was made up of small particles which meant that the atom was divisible

• It was proved that atoms were made up of three parts; protons, electrons and neutrons.

• It proved that atoms were neutral

J.J Thomson and the Atomic Theory

Awarded the Nobel Prize in 1906 Was knighted by King Edward VII Wrote many other scientific novels and

articles mostly about physics, but also one memoir

Other Accomplishments

• http://www.nobelprize.org/nobel_prizes/physics/laureates/1906/thomson-bio.html

• http://www.nndb.com/people/479/000099182/• http://www.aip.org/history/electron/jjthomson.htm• http://www.biography.com/people/jj-thomson-4003

9• http://web.lemoyne.edu/giunta/EA/THOMSONann.

HTML• http://www.aip.org/history/electron/jjhome.htm• http://www.tutorvista.com/science/jj-thomson-ato

mic-theory-0

Bibliography