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Question
An ideal diode should pass a current freely in one direction and should stop it completely in the opposite direction. Which is closer to ideal-vacuum diode or a p-njunction diode?
Solution
It should be an ideal vacuum diode. When a pn junction diode is reverse biassed then a small current called reverse current flows across the diode.As the the p‒n junction diode allows some current in reverse biassed condition also so the given diode can not be a pn junction diode.
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