AIIMS Physics Semiconductor Electronics Materialsdevices Simple Circuits Class 12 Questions

If voltage across zener diode is 6V then find out value of maximum resistance in this condition.

The given transistor operates in saturation region then what should the be value of $\text{V}_{\text{BB}}$: $$\left(\text{R}_{\text{out}} = 200\ \Omega,\ \text{R}_{\text{in}} = 100\text{ k}\Omega,\ \text{V}_{\text{CC}} = 3\text{ volt},\ \text{V}_{\text{BE}} = 0.7\text{ volt},\ \text{V}_{\text{CE}} = 0,\ \beta = 200\right)$$

Assertion: Photodiode and solar cell work on same mechanism. Reason: Area is large for solar cell.

Assertion : Photodiode and solar cell work on same mechanism. Reason : Area is large for solar cell.

Assertion : Photodiode current work in reverse bias. Reason : Change in diode increases with increase in intensity.

What is the voltage gain in a common emitter amplifier, where input resistance is 3Ω and load resistance 24Ω, β = 0.6?

When an impurity is doped into an intrinsic semiconductor, the conductivity of the semiconductor

A pure semiconductor has equal electron and hole concentration of 10¹⁶ m⁻³. Doping by gallium increases nₕ to 5×10²² m⁻³. Then, the value of nₑ in the doped semiconductor is

Assertion: An N-type semiconductor has a large number of electrons but still it is electrically neutral. Reason: An N-type semiconductor is obtained by doping an intrinsic semiconductor with a pentavalent impurity.

Assertion: Electron has higher mobility than hole in a semiconductor. Reason: Mass of electron is less than the mass of hole.

Assertion : A transistor is a voltage operating device. Reason : Base current is greater than the collector current.

Assertion: A N type semiconductor has a large number of electrons but still it is electrically neutral. Reason: A N type semiconductor is obtained by doping an intrinsic semiconductor with a pentavalent impurity.

Which of the following logic gate has only one input and one output?

In a full wave rectifier in which input voltage is represented by V = Vₘ sin ωt, then peak inversion voltage of non conducting diode will be:

An N-P-N transistor is connected in common emitter configuration in which collector supply is $9\text{ V}$ and the voltage drop across the load resistance of $1000\ \Omega$ connected in the collector circuit is $1\text{ V}$. If current amplification factor is $(25/26)$, If the internal resistance of the transistor is $200\ \Omega$, then which of the following options is correct.

A semiconductor having electron and hole mobilities μₙ and μₚ respectively. If its intrinsic carrier density is nᵢ, then what will be the value of hole concentration P for which the conductivity will be minimum at a given temperature?

In a solar cell current is generated due to bond breakage in which region.

What is the conductivity of a semiconductor, if electron density $= 5 \times 10^{12}\text{ / cm}^3$ and hole density $= 8 \times 10^{13}\text{ / cm}^3$ ($\mu_e = 2.3\text{ m}^2\text{ V}^{-1}\text{ s}^{-1}, \mu_h = 0.01\text{ m}^2\text{ V}^{-1}\text{ s}^{-1}$)

Suppose a ‘n’-type wafer is created by doping $\text{Si}$ crystal having $5 \times 10^{28}\text{ atoms/m}^3$ with $1\text{ ppm}$ concentration of $\text{As}$. On the surface $200\text{ ppm}$ Boron is added to create ‘P’ region in this wafer. Considering $n_i = 1.5 \times 10^{16}\text{ m}^{-3}$ calculate the density of the minority charge carriers in the $p$ regions.

A silicon diode has a threshold voltage of 0.7 V. If an input voltage given by 2 sin (πt) is supplied to a half wave rectifier circuit using this diode, the rectified output has a peak value of

For the given CE biasing circuit, if voltage across collector-emitter is $12\text{ V}$ and current gain is $100$ and base current is $0.04\text{ mA}$, then determine the value collector resistance $R_C$.

Assertion : Gallium arsenide phosphide is used in red L.E.D. Reason : Its work function lies b/w 1.65 ev.

Assertion: The current gain in common base circuit is always less than one. Reason: At constant collector voltage the change in collector current is more than the change in emitter current.

Assertion : A pure semiconductor has negative temperature coefficient of resistance. Reason : In a semiconductor on raising the temperature, more charge carriers are released, conductance increase and resistance decrease.

A specimen of silicon is to be made P⁻type semi-conductor for this one atom of indium, on an average, 5×10⁷ silicon atoms. If the number density of silicon is 5×10²² atom/m³. Then the number of acceptor atom per cm³ will be

A semiconductor has an electron concentration of 8×10¹³ per cm³ and a hole concentration of 5×10¹² per cm³. The electron mobility is 25000 cm²V⁻¹s⁻¹ and the hole mobility is 100 cm²V⁻¹s⁻¹. Then,

The proper combination of 3 NOT gate and 1 NAND gate is shown. If $A = 0, B = 1, C = 1$ then the output of the combination is,

The logic circuit as shown below has the input waveform A and B as shown pick out the correct output waveform.

A zener diode is specified as having a breakdown voltage of 9.1 V, with a maximum power dissipation of 364 mW. What is the maximum current the diode can handle?

A transistor connected at common emitter mode contains load resistance of 5 kΩ. If the input peak voltage is 5 mV and the current gain is 50, find the voltage gain.

In an intrinsic semiconductor band gap is 1.2 eV then ratio of number of charge carriers at 600 K and 300 K is

Given that the mobility of electrons in Ge is 0.4 m² V⁻¹ s⁻¹ and electronic charge is 1.6 × 10⁻¹⁹C. The number of donor atom (per m³) semiconductor of conductivity 500 mho/m is

The circuit as shown in figure, the equivalent gate is

Which of the following current must be zero in an unbiased PN junction diode?

In the given circuit, the voltage across the load is maintained at 12 V. The current in the zener diode varies from 0-50 mA. What is the maximum wattage of the diode?

For a common-emitter transistor, input current is 5 μA, β = 100 circuit is operated at load resistance of 10 kΩ, then voltage across collector emitter will be

Direction of electric field in P⁻N junction diode is

Assertion : Photodiode and photovoltaic cell are based on the same principle. Reason : Both use same method of operations to work.

Assertion : Transistor can be used as a switch. Reason : Both linear and non-linear voltage bias dependance occurs in it.

The logic gate represented in following figure is

Assertion: A pure semiconductor has negative temperature coefficient of resistance. Reason: On raising the temperature, more charge carriers are released, conductance increases and resistance decreases.

Assertion: At a fixed temperature, silicon will have a minimum conductivity when it has a smaller acceptor doping. Reason: The conductivity of an intrinsic semiconductor is slightly higher than that of a lightly doped p-type.

When the inputs of a two input logic gate are 0 and 0, the output is 1. When the inputs are 1 and 0, the output is zero. The type of logic gate is

Assertion : A photocell is called an electric eye. Reason : When light is incident on some semiconductor its electrical resistance is reduced.

Assertion : In a common-emitter amplifier, the load resistance of the output circuit is 1000 times the load resistance of the input circuit. If α = 0.98, then voltage gain is 49 × 10³. Reason : α = β / (¹⁺ β) (symbols have their usual meaning).

A Ge specimen is doped with Al. The concentration of acceptor atoms is ~ 10²¹ atoms/m³. Given that the intrinsic concentration of electron hole pairs is 10¹⁶/m³, the concentration of electrons in the specimen is

The forbidden gap in the energy bands of silicon is

Which of the following gates correspond to the truth table given below?

If collector current is 120 mA and base current is 2 mA and resistance gain is 3, what is power gain?

Zener diode acts as a/an