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Karnataka Board PUCPUC Science Class 11

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

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Question

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.

Short/Brief Note
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Solution

(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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Chapter 23: Semiconductors and Semiconductor Devices - MCQ [Page 418]

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HC Verma Concepts of Physics Vol. 2 [English] Class 11 and 12
Chapter 23 Semiconductors and Semiconductor Devices
MCQ | Q 2 | Page 418

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