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Thermionic Emission and Radioactivity — Physics STD 10 — Question

ICSE BoardEnglish MediumSTD 10PhysicsThermionic Emission and Radioactivity2 Marks
Question
State two characteristics of the substance used as thermionic emitter.
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Answer

(i) The substance must have high melting point.
(ii) The work function of the substance should be low so that electrons may be emitted even at low temperature.

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