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Question
The graph of potential barrier versus width of depletion region for an unbiased diode is shown in graph A. In comparison to A, graphs B and C are obtained after biasing the diode in different ways. Identify the type of biasing in B and C and justify your answer
| ‘A’ | ‘B’ | ‘C’ |
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Solution
B - reverse biased
In the case of a reverse-biased diode, the potential barrier becomes higher as the battery further raises the potential of the n side.
C - forward biased
Due to the forward bias connection, the potential of P side is raised and hence the height of the potential barrier decreases.
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