When a $PN$ junction diode is reverse biased,

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

In the given circuit,the current is $0.1 \ A$. The resistance of the $P-N$ junction is .... $\Omega$.

The potential barrier of a $P-N$ junction is $0.5 \ V$. The thickness of the depletion layer is $5.0 \times 10^{-7} \ m$. Calculate the electric field.

How does the height of the potential barrier change in forward bias and reverse bias?

In a $P-N$ junction under reverse bias,the depletion layer contains .......