Question

why the beam are called electrons​

Answer 1

Answer:

In 1906, Lee De Forest found that a small voltage on a grid of metal wires between the cathode and anode could control a much larger current in a beam of cathode rays passing through a vacuum tube. ... Cathode rays are now usually called electron beams.

Answer 2

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stream of electrons generated by heat reacts with strong charged atoms

so beams are called electrons

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