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Electric Current through Gases — Physics STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 SciencePhysicsElectric Current through Gases4 Marks
Question
Why does thermionic emission not take place in non-conductors?
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Answer

For thermionic emission, material should have low work function and large number of free electrons. But nonconductor does not have free electrons and they have higher work function. So, thermionic emission does not takes place in non-conductors.

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