Question

What was the hypothesis for e/m measurement experment you can come up with and did the data support the hypothesis? Were there any observations which surprised you?

Answer 1

The hypothesis for e/m measurement experiment was given by Thompson which is also known as Thompson’s hypothesis. Thompson's hypothesis was based on the electron’s existence. Thompson's hypothesis was based on the charge(e)-to-mass(m) ratio.

Thompson's hypothesis which was based on the charge(e)-to-mass(m) ratio leads to the concept of the first atomic particle.

In order to support the hypothesis it was seen that cathode rays are particles that carry a negative charge.In order to support the hypothesis the cathode rays exposed to a magnetic field and the cathode rays acted just like negative electric charges in motion. In addition to that, a metal was bombarded by cathode rays that acquires negative electrical charge and with that, The Thomson made the collection experiment in two sense one was conclusive and other was particularly elegant and by combining this two support the hypothesis.

It was surprising that e/m ratio found to be independent of speed and also neither the mass nor the charge of an ion depends on speed nor at ordinary speeds.