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Question
The cathode of a diode valve is replaced by another cathode of double the surface area. Keeping the voltage and temperature conditions the same, will the place current decrease, increase or remain the same?
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Solution
As the rate of emission of thermions is directly proportional to the surface area of the surface emitting it, the plate current doubles if the cathode of a diode valve is replaced by another cathode of double the surface area.Hence plate current increases.
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