WHy electrons are emitted from collector plate to emitter plate when it exposed to positive potential? what is the mechanism behind it?

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Solution

Dear Student,

Electrons in the atoms are continuously revolving around the nucleus in various orbits also called energy levels. When an electron acquires sufficient energy it jumps from a lower energy level or lower orbit to a higher energy level or higher orbit. The electron can also be imparted so much energy called ionisation energy so that it escapes from the atom. The energy can be supplied by many methods. One of the is by using a very high potential and causing electron emission from the cathode plate which is at negative potential to the anode plate which at a positive potential.

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