Class 12th Physics 2017 Set3 Delhi Board Paper Solution
Explain briefly with the help of necessary diagram, the forward and the reverse biasing of a p-n junction diode. Also, draw their characteristic curves in the two cases.
The diagram of the forward and reverse biasing of p-n junction diode is shown below:
Forward bias Reverse Bias
In forward bias P junction is connected to +ve, of emf and n with -ve, so that electric current flow due to majority carrier constituting forward current. Small increase in forward voltage show large increase in forward current so resistance is low. Depletion layer width decrease and barrier height is reduced.
In reverse bias P junction is connected to -ve of battery and n with positive. This cause effective barrier voltage enhancement VB + V. Resistance of P-n Junction in reverse bias is high.
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(d) The small ozone layer on top of the stratosphere is crucial for human survival. Why?
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Would you expect a greater or smaller dip angle in Britain?
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