For the diagram shown,the resistances between points $A$ and $B$ when the ideal diode $D$ is forward biased is $R_1$ and when it is reverse biased is $R_2$. The ratio $R_1: R_2$ is

Which of the following statements concerning the depletion zone of an unbiased $PN$ junction is (are) true?

Two sides of a semiconductor germanium crystal $A$ and $B$ are doped with arsenic and indium respectively. They are connected to a battery as shown in the figure. The correct graph between current and voltage for the arrangement is:

Consider a $p-n$ junction as a capacitor,formed with $p$ and $n$-materials acting as thin metal electrodes and depletion layer width acting as separation between them. Basing on this,assume that an $n-p-n$ transistor is working as an amplifier in $CE$ configuration. If $C_1$ and $C_2$ are the base-emitter and collector-emitter junction capacitances,then :

The circuit shown in the figure contains two diodes,each with a forward resistance of $30 \, \Omega$ and infinite backward resistance. If the battery is $3 \, V$,the current through the $50 \, \Omega$ resistance (in ampere) is

Avalanche breakdown is due to