Question

The electrical resistance of depletion layer is large because (A) it contains electrons as charge carriers (B) it has holes as charge carriers. (C) it has no charge carriers. (D) It has large number of charge carriers

Short answer

The correct reason for the large electrical resistance in the depletion layer is option (C) because it has no charge carriers.

Step-by-step solution

Analyze the first option

Option (A) states that the electrical resistance of the depletion layer is large because it contains electrons as charge carriers. This is not the correct reason because the presence of electrons as charge carriers would actually lead to electrical conduction, not an increase in resistance.

Analyze the second option

Option (B) states that the electrical resistance of the depletion layer is large because it has holes as charge carriers. This is also not the correct reason because, like electrons, the presence of holes as charge carriers would also lead to electrical conduction, not an increase in resistance.

Analyze the third option

Option (C) states that the electrical resistance of the depletion layer is large because it has no charge carriers. This is the correct reason because, in the depletion layer, the recombination of electrons and holes leaves behind a region with no charge carriers, thus resulting in a large electrical resistance.

Analyze the fourth option

Option (D) states that the electrical resistance of the depletion layer is large because it has a large number of charge carriers. This is not the correct reason because having a large number of charge carriers would lead to an increase in electrical conduction, not an increase in resistance.

Conclusion

Based on the analysis of each option, the correct reason for the large electrical resistance in the depletion layer is option (C) because it has no charge carriers.