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प्रश्न
In a p-n junction with open ends,
(a) there is no systematic motion of charge carries
(b) holes and conduction electrons systematically go from the p-side to n-side and from the n-side to p-side respectively
(c) there is no net charge transfer between the two sides
(d) there is a constant electric field near the junction.
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उत्तर
(b) holes and conduction electrons systematically go from the p-side to n-side and from the n-side to p-side, respectively
(c) there is no net charge transfer between the two sides
(d) there is a constant electric field near the junction
Because of the difference in the concentration of charge carriers in the p−n junction, holes from the p side move to the n side and electrons from the n side move to the pside. This motion of charge carriers gives rise to diffusion current.
Because of this, a negative space charge region is formed in the p region and a positive space region is formed in the n region. This sets up an electric field across the junction. Thus, there is a constant electric field near the junction.
This electric field further opposes the diffusion of majority charge carriers across the junction. As a result, an electron from the p region starts moving to the n region and a hole from the n region starts moving to the p region. This sets up drift current. Thus, there is a systematic flow of charge carriers across the junction. Also, there is no net charge transfer between the two sides.
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संबंधित प्रश्न
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In a p-n junction,
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(d) holes and conduction electrons recombine continuously throughout the material except in the depletion region.
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(c) an n-type semiconductor
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The potential barrier existing across an unbiased p-n junction is 0.2 volt. What minimum kinetic energy a hole should have to diffuse from the p-side to the n-side if (a) the junction is unbiased, (b) the junction is forward-biased at 0.1 volt and (c) the junction is reverse-biased at 0.1 volt?
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(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
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Choose the correct option.
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p-n junction diode is formed
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