Cathode Rays Experiment some missunderstood parts

AI Thread Summary
J.J. Thomson's cathode ray experiments aimed to establish the nature of cathode rays, ultimately proving they are negatively charged particles. The first experiment demonstrated that the rays produced a charge detected by an electrometer but did not confirm that the rays themselves carried the charge. The second experiment confirmed that the rays were deflected by an electric field, providing evidence that they were indeed charged particles. The third experiment allowed Thomson to calculate the mass-to-charge ratio of these particles, solidifying their identification as particles. This sequence of experiments clarified misconceptions about the properties of cathode rays and their charge.
Maisara-WD
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Hi all

I don't know If this is the suitable section for this post.. but at all.. let's see if anybody can make me understand this :):)

You all know of course J.J. Thomsons's three CRT experiments...

The first one was aiming to prove that the appearing rays and the negative charges detected by the electrometer are inseperable and interwined, and that was by exposing them to a magnetic field, observed that the rays were bent and no readings were recorded on the electrometer.. so they proved it well... but please.. isn't that meaning that the rays carry -ve charge?? so what's the aim of the 2nd exp.?
My personal understanding is that the 2nd exp. is to find a solution for the problem of rays being not deflected by electric field and not to prove anything.. BUT

In the second exp. Thomson found a solution for the problem and -I don't know how..- he concluded that the rays are particles -vely chraged... How this differs from the first exp. Does the magnetic field differs physically from the electric field -I mean in attracting charged bodies-? doesn't the attraction by magnet prove that the rays are -vely chraged particles??

I'm Waiting ;)
 
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The second experiment proved that the rays were deflected by an electric field.
Other workers had failed to find this - leading them to believe that the beam perhaps did not consist of charged particles.

Thompson's first experiment showed that the beam produced charge at the electrometer - it did not prove that the charge was carried by the beam.
The second confirmed that the beam itself carried charge.
The third allowed him to actually calculate the ratio of mass to charge of the particles in the beam. Showing in fact that they were particles.
 
AJ Bentley said:
The second experiment proved that the rays were deflected by an electric field.
Other workers had failed to find this - leading them to believe that the beam perhaps did not consist of charged particles.

Thompson's first experiment showed that the beam produced charge at the electrometer - it did not prove that the charge was carried by the beam.
The second confirmed that the beam itself carried charge.
The third allowed him to actually calculate the ratio of mass to charge of the particles in the beam. Showing in fact that they were particles.

Thank You very very much.. I'm very grateful to u
 
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