Coating of strontium oxide on Tungsten cathode in a valve is good for – McqOptions

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1.	Coating of strontium oxide on Tungsten cathode in a valve is good for thermionic emission because [RPMT 1998]
A.	Work function decreases
B.	Work function increases
C.	Conductivity of cathode increases
D.	Cathode can be heated to high temperature
Answer» B. Work function increases

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