In an unbiased n-p junction electrons diffuse from n - region to p - region because :
holes in p - region attract them
electrons travel across the junction due to potential difference
electron concentration in n - region is more as compared to that in p - region
only electrons move from n to p region and not the vice - versa
As we learnt in
P -N junction as diode -
It is a one way device. It offers a low resistance when forward biased and high resistance when reverse biased.
- wherein
R = 0, Forward
R Reverse
In unbiased p-n junction, electron diffuse from n region to p region because of concentration gradient.
Correct option is 3.
Option 1)
holes in p - region attract them
This is an incorrect option.
Option 2)
electrons travel across the junction due to potential difference
This is an incorrect option.
Option 3)
electron concentration in n - region is more as compared to that in p - region
This is the correct option.
Option 4)
only electrons move from n to p region and not the vice - versa
This is an incorrect option.
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