"To emit a free electron from a metal surface a minimum amount of energy must be supplied" For metal A (tungsten) - work function is 4.52 eV for metal B (thoriated tungsten) it is 2.6 ev, for metallic (oxide coated tungsten) it is 1 eV Which will you prefer as a good electron emitter and why?

"To emit a free electron from a metal surface a minimum amount of ener

1.	"To emit a free electron from a metal surface a minimum amount of energy must be supplied" For metal A (tungsten) - work function is 4.52 eV for metal B (thoriated tungsten) it is 2.6 ev, for metallic (oxide coated tungsten) it is 1 eV Which will you prefer as a good electron emitter and why?
Answer» Solution :Work function for metallic OXIDE coated tungsten is small (1EV.) Hence this material is GOOD elec TRON emitter

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"To emit a free electron from a metal surface a minimum amount of energy must be supplied" For metal A (tungsten) - work function is 4.52 eV for metal B (thoriated tungsten) it is 2.6 ev, for metallic (oxide coated tungsten) it is 1 eV Which will you prefer as a good electron emitter and why?

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