What was jj thomsons experiment

Search this site. Dalton's Atomic Theory. Thomson's Experiment. Millikan's Experiment. Rutherford's Experiment. Chadwick's Discovery. The Nucleus. Atomic Mass Unit. Periodic Trends. This led to one of his other famous discoveries in when he channeled a stream of ionized neon through a magnetic and an electric field and used deflection techniques to measure the charge to mass ratio.

In doing so, he discovered that neon was composed of two different kinds of atoms, and proved the existence of isotopes in a stable element. This was the first use of mass spectrometry. Thomson married Rose Paget, one of his students, in They had one daughter, Joan, and one son, George Paget Thomson, who went on to become a physicist and win a Nobel Prize of his own. Thomson published 13 books and more than papers in his lifetime.

He left research in to become Master of Trinity College. We strive for accuracy and fairness. If you see something that doesn't look right, contact us! Subscribe to the Biography newsletter to receive stories about the people who shaped our world and the stories that shaped their lives. Later and improved cathode ray experiments found that certain types of glass produced a fluorescent glow at the positive end of the tube. However, other researchers, notably Crookes, argued that the focused nature of the beam meant that they had to be particles.

Physicists knew that the ray carried a negative charge but were not sure whether the charge could be separated from the ray. They debated whether the rays were waves or particles, as they seemed to exhibit some of the properties of both. In response, J. Thomson constructed some elegant experiments to find a definitive and comprehensive answer about the nature of cathode rays.

His first experiment was to build a cathode ray tube with a metal cylinder on the end. This cylinder had two slits in it, leading to electrometers, which could measure small electric charges. He found that by applying a magnetic field across the tube, there was no activity recorded by the electrometers and so the charge had been bent away by the magnet.

This proved that the negative charge and the ray were inseparable and intertwined. Like all great scientists, he did not stop there, and developed the second stage of the experiment, to prove that the rays carried a negative charge.

To prove this hypothesis, he attempted to deflect them with an electric field. Earlier experiments had failed to back this up, but Thomson thought that the vacuum in the tube was not good enough, and found ways to improve greatly the quality. For this, he constructed a slightly different cathode ray tube, with a fluorescent coating at one end and a near perfect vacuum.

Halfway down the tube were two electric plates, producing a positive anode and a negative cathode, which he hoped would deflect the rays. As he expected, the rays were deflected by the electric charge, proving beyond doubt that the rays were made up of charged particles carrying a negative charge.

In Thomson published an influential monograph urging chemists to use the mass spectrograph in their analyses. Thomson received various honors, including the Nobel Prize in Physics in and a knighthood in He also had the great pleasure of seeing several of his close associates receive their own Nobel Prizes, including Rutherford in chemistry and Aston in chemistry Access more than , print volumes, rare books and manuscripts, archival materials, and historical photographs.

Explore the oral history collection at the Science History Institute, with interviews dating back to Thanks to J.