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प्रश्न
In an unbiased p-n junction, holes diffuse from the p-region to n-region because ______.
विकल्प
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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उत्तर
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.
संबंधित प्रश्न
In a p-n junction diode, the current I can be expressed as
I = `"I"_0 exp ("eV"/(2"k"_"BT") - 1)`
where I0 is called the reverse saturation current, V is the voltage across the diode and is positive for forward bias and negative for reverse bias, and I is the current through the diode, kBis the Boltzmann constant (8.6×10−5 eV/K) and T is the absolute temperature. If for a given diode I0 = 5 × 10−12 A and T = 300 K, then
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(d) there is a constant electric field near the junction.
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