The forbidden energy gap of $Ge$ is $0.75 \ eV$. The maximum wavelength of incident photon radiation that can generate an electron-hole pair in a $Ge$ semiconductor is ........... $\mathring{A}$.

$A$ 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 $= 1.6 \times 10^{-19} \,C$.)

In the circuit shown, assume the diode to be ideal. When $V_{i}$ increases from $2 \ V$ to $6 \ V$, the change in the current is (in $mA$):

$A$ silicon diode has a forward voltage drop of $1.2\, V$ for a forward $DC$ current of $100\, mA$. It has a reverse current of $1\times10^{-6}\, A$ for a reverse voltage of $10\, V$. The bulk and reverse resistances of the diode are:

Find the current $i$ in the circuit shown.

In the circuit shown for the given input voltage $V_i$, the maximum output voltage $V_0$ is