Solving Problems on Charge Quantisation – J. J. Thomson’s experiments

This video presents a set of problems and their solutions on the topic of Charge quantisation - J.J. Thomson's experiments leading to the discovery of the electron. J.J. Thomson's famous experiments on cathode rays not only led to the discovery of the electron, but these experiments also gave clues to the existence of the electrons within the atom thereby leading to more definite theories on the structure of the atom. Among the three well noted experiments performed by J.J. Thomson during the 1890's, the third experiment performed around 1897 led to the discovery of the electron. These experiments not only unveiled the then mysterious cathode rays but also provided evidence for the quantisation of the electric charge based on the fundamental charge which is the charge on the electron thereby confirming charge quantisation. Thus Thomson's experiments played a significant role in the historical development of Modern Physics in general and Quantum Theory in particular. The problems discussed in this video are generally at the undergraduate level and belong to varying difficulty levels. Each problem question is discussed and the approach to solving it is provided in detail. Students preparing for competitive exams such as the IIT-JEE or the NEET from India may also find the problems discussed in this video useful. It is sincerely hoped that Undergraduate Physics/B.Sc. Physics/B.S Physics students would find strong encouragement to take up Physics learning through problems with videos such as this.