When a $p-n$ diode is reverse biased,then

The built-in potential of a $p-n$ junction diode is $0.7 \,V$. If the diode is forward biased and the applied voltage is $0.3 \,V$, the effective barrier height is (in $\,V$)

In the given figure,which of the diodes are forward biased?

In the diagram shown, the resistance between points $A$ and $B$ is '$R_1$' when an ideal diode $D$ is forward biased and is '$R_2$' when ideal diode $D$ is reverse biased. The ratio $R_1/R_2$ is

$A$ $2\,V$ battery is connected across $AB$ as shown in the figure. The value of the current supplied by the battery when in one case the battery's positive terminal is connected to $A$ and in the other case when the positive terminal of the battery is connected to $B$ will respectively be:

In a $P-N$ junction,avalanche current flows in the circuit when the biasing is: