The depletion layer in $p-n$ junction region is caused by

The characteristic graph of a diode at different temperatures is shown. What is the relationship between the temperatures?

If the $p-n$ junction diode is unbiased,

An electron in the $n$-region of a $p-n$ junction moves towards the junction with a speed of $5 \times 10^5 \ m/s$. If the barrier potential of the junction is $0.45 \ V$,then the speed with which the electron enters the $p$-region after penetration through the barrier is (Charge of the electron $e = 1.6 \times 10^{-19} \ C$ and mass of the electron $m = 9 \times 10^{-31} \ kg$).

In order to forward bias a $PN$ junction,the negative terminal of the battery is connected to

Currents flowing in each of the following circuits $A$ and $B$ respectively are