Find $V_{AB}$ in the given circuit.

In the case of forward biasing of a $PN-$ junction,which one of the following figures correctly depicts the direction of flow of charge carriers?

For an ideal diode,in forward and reverse biased condition the resistance is respectively

Two identical $P-N$ junctions are connected in series with a battery in three ways as shown in the figure. In which two circuits will the potential difference across the $P-N$ junctions be equal?

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

$A$ potential barrier of $0.4 \,V$ exists across a p-n junction. An electron enters the junction from the $n$-side with a speed of $6.0 \times 10^{5} \,ms^{-1}$. The speed with which the electron enters the $p$-side will be $\frac{x}{3} \times 10^{5} \,ms^{-1}$. The value of $x$ is ..............
(Given: mass of electron $= 9 \times 10^{-31} \,kg$,charge on electron $= 1.6 \times 10^{-19} \,C$.)