$A$ circuit and the signal applied at its input terminal $(V_i)$ are shown in the figure below. Which one of the options correctly describes the output waveform $(V_0)$? (Assume all the devices used are ideal and take $P$ as the reference potential.)

$A$ diode is connected to $220 \, V \, (rms) \, ac$ in series with a capacitor as shown in the figure. The voltage across the capacitor is

Which of the following circuits represents a forward biased diode? Choose the correct answer from the options given below.

In the figure shown, if the diode forward voltage drop is $0.2 \, V$, the voltage difference between $A$ and $B$ is (in $V$)

The curve between charge density and distance near a $P-N$ junction will be:

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 :