The following are the graphs of potential barrier versus width of the depletion region for a p-n junction diode.

Which of the following is correct?

In a given semiconductor, the ratio of the number density of electron to number density of hole is $$2: 1$$. If $$\frac{1}{7}$$th of the total current is due to the hole and the remaining is due to the electrons, the ratio of the drift velocity of holes to the drift velocity of electrons is :

An ideal diode is connected in series with a capacitor. The free ends of the capacitor and the diode are connected across a $$220 \mathrm{~V}$$ ac source. Now the potential difference across the capacitor is :

Though $$\mathrm{Sn}$$ and $$\mathrm{Si}$$ are $$4^{\text {th }}$$ group elements, $$\mathrm{Sn}$$ is a metal while $$\mathrm{Si}$$ is a semiconductor because