Question 6: Semiconductors and Logic Gates

Question

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason $\mathbf{R}$
Assertion A :
A diode under reverse-biased condition provides very small current which is nearly independent of voltage until a critical limit at which the current increases drastically.
Reason R :
Below the critical voltage limit, only majority charge carriers flow which increases drastically above critical voltage.
choose the correct answer from the options given below

Accepted Answer

The assertion is true.
In a reverse-biased diode, the current is very small and remains almost constant with increase in reverse voltage. This small current is called reverse saturation current. When the reverse voltage reaches a critical value called breakdown voltage, the current increases sharply.
So, Assertion A is correct.
Now consider the reason.
In reverse bias, the current below breakdown is due to minority charge carriers, not majority charge carriers. Majority carriers are pulled away from the junction in reverse bias and do not contribute to the small reverse current. Hence the statement in Reason R is false.
Therefore, the correct option is:
$$\boxed{	ext{Option C: A is true but R is false}}$$

Answer

Both $\mathbf{A}$ and $\mathbf{R}$ are true and $\mathbf{R}$ is the correct explanation of $\mathbf{A}$

Answer

Both $\mathbf{A}$ and $\mathbf{R}$ are true but $\mathbf{R}$ is NOT the correct explanation of $\mathbf{A}$

Answer

A is true but $\mathbf{R}$ is false

Answer

A is false but $\mathbf{R}$ is true

Semiconductors and Logic Gates

Choose the correct answer: