Why construction of LED is similar to the normal p-n junction diode?

Identify the semiconductor devices whose characteristics are given below, in the order $\left(\mathrm{a}\right),\mathrm{ }\left(\mathrm{b}\right),\mathrm{ }\left(\mathrm{c}\right),\mathrm{ }\left(\mathrm{d}\right)$:

What is the advantage of an LED bulb over filament bulb?

The value of the resistor, $R_S$, needed in the DC voltage regulator circuit shown here, equals:

Take the breakdown voltage of the zener diode used in the given circuit as $6 \mathrm{V}$. For the input voltage shown in the figure below, the time variation of the output voltage is: (Graphs drawn are schematic and not to the scale)

A $220 \mathrm{V}$ A.C. supply is connected between points $A$ and $B$ as shown in figure what will be the potential difference $V$ across the capacitor?

$Ge$ and $Si$ diodes start conducting at $0.3 V$ and $0.7 V$ respectively. In the following figure if $Ge$ diode connection are reversed, the value of $V_0$ changes by: (assume that the Ge diode has large breakdown voltage)

In the given circuit, The current through battery is

Two Zener diodes ($A$ and $B$) having breakdown voltages of $6 \mathrm{V}$ and  $4 \mathrm{V}$ respectively, are connected as shown in the circuit below. The output voltage $V_0$ variation with input voltage linearly increasing with time, is given by ($V_{input} = 0 \mathrm{V} \text{at} t = 0$)

In the following circuit diagram, the current through the battery is

What will be the current flowing through the $6 \mathrm{k\Omega }$ resistor in the circuit shown, where the breakdown voltage of the Zener is $6 \mathrm{V}?$

Two $p$ - $n$ photodiodes are fabricated from semiconductors with band gap of $2.8\mathrm{eV}$ and $2.6\mathrm{eV},$ respectively.

Choose the correct statement from the following.

Identify the electronic components from the following symbols. Write any one difference between them.