Identify the solar cell characteristics from the following options.

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

$A$ $PN-$ junction has a thickness of the order of

In the case of forward biasing of a $p-n$ junction diode,which one of the following figures correctly depicts the direction of conventional current (indicated by an arrow mark)?

The voltage-current characteristic of a diode during forward bias is given by $I = 7.8 \times 10^{-5} e^{6.5 V_D}$, where $I$ is the current in $mA$ and $V_D$ is the diode voltage in $V$. Find the dynamic resistance of the diode in $\Omega$, when the current is $4 \ mA$.

In the given circuit, the voltage across load resistance $(R_L)$ is: (in $V$)