A p-n photodiode is made of a material with a band gap of $2.0\text{ eV}$. The minimum frequency of the radiation that can be absorbed by the material is nearly:

In the following figure, the diodes which are forward biased, are (I) (II) (III) (IV). Choose the correct option from the given ones:

An n-p-n transistor is connected in the common base configuration in a given amplifier. A load resistance of $800\, \Omega$ is connected in the collector circuit and the voltage drop across it is $0.8\text{ V}$. If the current amplification factor is $0.96$ and the input resistance of the circuit is $192\, \Omega$, the voltage gain and the power gain of the amplifier will respectively be:

In a common-emitter transistor amplifier, the audio signal voltage across the collector is $3\text{ V}$. The resistance of the collector is $3\text{ k}\Omega$. If the current gain is $100$ and the base resistance is $2\text{ k}\Omega$, the voltage and power gain of the amplifier are:

If in a p-n junction, a square input signal of $10 \text{ V}$ is applied as shown, then the output across $R_L$ will be:

For transistor action: (a) the base, emitter and collector regions should have similar size and doping concentrations. (b) the base region must be very thin and lightly doped. (c) the emitter-base junction is forward biased and the base-collector junction is reverse biased. (d) both the emitter-base junction as well as the base-collector junction are forward biased. Which of the following pairs of statements is correct?

A p-n photodiode is fabricated from a semiconductor with a band gap of $2.5 \text{ eV}$. It can detect a signal of wavelength:

Which one of the following statements is false?

Pure $\text{Si}$ at $500\text{ K}$ has an equal number of electron ($n_e$) and hole ($n_h$) concentration of $1.5 \times 10^{16} \text{ m}^{-3}$. Doping by indium increases the hole concentration $n_h$ to $4.5 \times 10^{22} \text{ m}^{-3}$. The doped semiconductor is of: