In reverse bias condition of photodiode, the change in saturation reverse current is directly proportional to the change in the incident light flux or light intensity, which can be measured accurately. It is not so when photodiode is forward bias.
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: Photodiodes are preferably operated in reverse bias condition for light intensity measurement.
Reason R: The current in the forward bias is more than the current in the reverse bias for a p−n junction diode.
In the light of the above statement, choose the correct answer from the options given below :
Held on 24 Jan 2023 · Verified 6 Jul 2026.
A is false but R is true
Both A and R are true but R is NOT the correct explanation of A
A is true but R is false
Both A and R are true and R is the correct explanation of A
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Two p-n junction diodes $D_{1}$ and $D_{2}$ are connected as shown in figure. $A$ and $B$ are input signals and $C$ is the output. The given circuit will function as a $\_\_\_\_$. 
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The given circuit works as : 
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