J.J. Thomson was a British physicist who conducted experiments on cathode rays in 1897. His experiment was a significant discovery in the field of physics, which helped in the development of modern-day electronics. Thomson’s experiment was conducted using a cathode ray tube, which is a vacuum tube consisting of a cathode and an anode.


Thomson’s experiment was conducted in three steps:

1. He passed an electric current through a cathode ray tube containing a low-pressure gas.
2. A cathode ray was produced, which traveled from the cathode to the anode.
3. Thomson placed two electrodes in the tube, which allowed him to measure the voltage and current of the cathode ray.


Thomson made several observations during the experiment:

1. The cathode ray was deflected by an electric field, which suggested that it was made up of negatively charged particles.
2. The cathode ray was also deflected by a magnetic field, which suggested that it was made up of charged particles.
3. The ratio of the charge to the mass of the cathode ray particles was very small, which suggested that they were subatomic particles.


Thomson’s cathode ray tube experiment helped in the discovery of electrons, which are subatomic particles with a negative charge. His experiment also helped in the development of modern-day electronics, including television screens and computer monitors. Thomson’s discovery of electrons earned him the Nobel Prize in Physics in 1906.

In conclusion, J.J. Thomson’s cathode ray tube experiment was a significant discovery in the field of physics. It helped in the discovery of electrons and the development of modern-day electronics.