Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R Assertion A : Photodiodes are used in forward bias usually for measuring the light intensity. Reas

Question

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R

Assertion A: Photodiodes are used in forward bias usually for measuring the light intensity.

Reason R: For a $p - n$ junction diode, at applied voltage $V$ the current in the forward bias is more than the current in the reverse bias for $|V_{z}| > \pm V \geq |V_{0}|$ where $V_{0}$ is the threshold voltage and $V_{z}$ is the breakdown voltage.

In the light of the above statements, choose the correct answer from the options given below

TestHub · Accepted Answer

Photodiodes are operated in reverse bias condition. The change in saturation reverse current in a photodiode with reverse bias is directly proportional to the change in light intensity, thus can be precisely measured.

Current in forward bias (for applied voltage $V \geq V_{0}$ ) is always greater than current in reverse bias (for $V \leq V_{z}$ ) in a $p - n$ junction diode.

Hence, Assertion if false but Reason is true.

Physics - Semiconductors Question with Solution | TestHub

Options:

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