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Question
In an unbiased p-n junction, holes diffuse from the p-region to n-region because ______.
Options
free electrons in the n-region attract them.
they move across the junction by the potential difference.
hole concentration in p-region is more as compared to n-region.
All the above.
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Solution
Hole concentration in p-region is more as compared to n-region.
Explanation:
The diffusion of charge carriers across a junction takes place from the region of higher concentration to the region of lower concentration. In this case, the p-region has a greater concentration of holes than the n-region. Hence, in an unbiased p-n junction, holes diffuse from the p-region to the n-region.
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