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When I was learning photoelectric effect, It was told that Photons incident on metallic plate in vacuum causes electron to emit if the energy of photon is greater than work function of metal, In this case to me, The emitted electrons in vacuum seemed like a similar condition like that of cathode ray tube, can these emitted electrons be called cathode rays and will they have all properties similar to cathode rays?

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The name "Cathode Rays" (see https://en.wikipedia.org/wiki/Cathode_ray) was invented in 1876 for the "rays" coming out of a cathode (electrode connected to the negative side of the electric source), before anybody knew what these were. In 1897 Thompson discovered that these "rays" were a stream of negatively charged particles, each about 1800 times lighter than a hydrogen atom (Thomspson received the Nobel prize of this discovery). The name adopted for these particles was electrons, and this is what we call them today.

Today you should stick to the name "electrons", and avoid the name "cathode rays" that was used before scientists understood what they were. In some historic uses, where an actual vacuum tube was involved with an actual cathode, the name "cathode rays" was still used (especially in those old "CRT" televisions and displays - https://en.wikipedia.org/wiki/Cathode-ray_tube). But it shouldn't be used to refer to electrons in other contexts.

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No, emitted electrons in the photoelectric effect can not be reffered to as "cathode rays." Cathode rays are a stream of electrons that are emitted from the cathode of a vacuum tube when it is subjected to a high voltage. These electrons are produced as a result of thermionic emission or other electron-emitting processes from the cathode material.

In the photoelectric effect, electrons are emitted from a material when it is exposed to light or electromagnetic radiation. These emitted electrons are reffered to as "photoelectrons" The photoelectric effect is a different phenomenon from cathode rays and is typically characterized by the interaction of photons (light quanta) with the material's electrons, leading to the ejection of electrons from the material's surface.

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