Semiconductor Devices and Logic Gates · Physics · MHT CET

In semiconductors at room temperature,

The logic circuit in figure is equivalent to...

In an NPN transistor $10^{10}$ electrons enter the emitter in $10^{-6} \mathrm{~s}$ and $2 \%$ electrons recombine with holes in base. The current rat...

The output of following combination is same as that of ...

In an n-p-n transistor, the collector current is $$28 \mathrm{~mA}$$. If $$80 \%$$ of electrons reach the collector, its base current in $$\mathrm{mA}...

When the conductivity of a semiconductor is only due to the breaking of the covalent bonds, the semiconductor is called

For a common emitter configuration, if '$$\alpha$$' and '$$\beta$$' have their usual meanings, the incorrect relation between '$$\alpha$$' and '$$\bet...

For emission of light, a light emitting diode (LED) is

In semiconductors at room temperature,

The Boolean expression for the following combination is ...

If the maximum efficiency of a full wave rectifier is $$x \%$$ and that of half-wave rectifier is $$y \%$$, then the relation between $$x$$ and $$y$$ ...

Doping of a semiconductor (with small impurity atoms) generally changes the resistivity as follows.

The following graph represents ...

If two inputs of a NAND gate are shorted, the resulting gate is

On increasing the reverse bias to a large value in a P-N junction diode, current

In the following digital logic circuit, the output Y will be '1' for inputs ...

Which one of the following statements is WRONG regarding LED?

In which figure, the junction diode is forward biased?

The following logic gate combination is equivalent to ...

The logic gate combination circuit shown in the figure performs the logic function of ...

When forward bias is applied to a p-n junction, then what happens to the potential barrier $$\left(V_B\right)$$ and the width $$(\mathrm{X})$$ of the ...

In the study of transistor as an amplifier if $$\alpha=\frac{I_C}{I_E}=0.98$$ and $$\beta=\frac{I_C}{I_B}=49$$, where $$I_C, I_B$$ and $$\mathrm{I}_{\...

If $$p$$-$$n$$ junction diode is in forward bias then

In the digital circuit the inputs are as shown in figure. The Boolean expression for output $$\mathrm{Y}$$ is ...

Identify the correct circuit diagrams for the normal operation from the following. ...

In energy band diagram of insulators, a band gap and the conduction band is respectively

In the case of NAND gate, if A and B are the inputs and $$\mathrm{Y}$$ is the output then

A pure $$\mathrm{Si}$$ crystal has $$4 \times 10^{28}$$ atoms per $$\mathrm{m}^3$$. It is doped by 1 ppm concentration of antimony. The number of free...

The output of an 'OR' gate is connected to both the inputs of a 'NAND' gate. The combination will serve as

Which one of the operations of $$\mathrm{n}-\mathrm{p}-\mathrm{n}$$ transistor differs from that of $$p-n-p$$ transistor?

For the diagram shown, the resistances between points A and B when ideal diode D is forward biased is '$$R_1$$' and that when reverse biased is '$$R_2...

To obtain the truth-table shown, from the following logic circuit, the gate G should be ...

In insulators

Identify the mismatch out of the following.

In the reverse biasing of a p-n junction diode :

In a transistor, in common emitter configuration, the ratio of power gain to voltage gain is

If the frequency of the input voltage is $$50 \mathrm{~Hz}$$, applied to a (a) half wave rectifier and (b) full wave rectifier. The output frequency i...

For an intrinsic semiconductor $$\left(\mathrm{n}_{\mathrm{h}}\right.$$ and $$\mathrm{n}_{\mathrm{e}}$$ are the number of holes per unit volume and nu...

A $$5.0 \mathrm{~V}$$ stabilized power supply is required to be designed using a $$12 \mathrm{~V}$$ DC power supply as input source. The maximum power...

To get the truth table shown, from the following logic circuit, the Gate G should be ...

For a NAND gate, the inputs and outputs are given below. .tg {border-collapse:collapse;border-spacing:0;} .tg td{border-color:black;border-style:sol...

The given circuit has two ideal diodes $$D_1$$ and $$D_2$$ connected as shown in the figure. The current flowing through the resistance $$R_1$$ will b...

Choose the correct statement. In conductors

For a transistor, the current ratio $$\alpha_{\mathrm{dc}}=\frac{69}{70}$$, the current gain $$\beta_{\mathrm{dc}}$$ is

The input a.c. voltage of frequency $$60 \mathrm{~Hz}$$ is applied to half-wave rectifier and also to full-wave rectifier. The output frequency in cas...

A p-n junction photodiode is fabricated from a semiconductor with a band gap of $$2.5 \mathrm{~eV}$$. It can detect a signal of wavelength [Planck's c...

For the output of the following logic circuit to be 'I', the values of inputs A and B should be respectively ...

Two identical ideal diodes are connected to an ammeter and a d.c source (1 volt) as shown. In which one of the following circuits, ammeter will not sh...

When the temperature of a semiconductor is increased, its resistance and electric conductivity respectively.

For a two input AND gate, the four entries are shown in the truth table. Identify the correct ones out of these $$(\mathrm{A}, \mathrm{B}=$$ input, $$...

In a CE transistor, a change of $$8.0 \mathrm{~mA}$$ in the emitter current produces a change of $$7.8 \mathrm{~mA}$$ in the collector current. What c...

The resultant gate and its Boolean expression in the given circuit is ...

What are the values of the currents flowing in each of the following diode circuits $$\mathrm{X}$$ and $$\mathrm{Y}$$ respectively? (Assume that the d...

In common emitter amplifier, a change of 0.2 mA in the base current causes a change of 5 mA in the collector current. If input resistance is 2 k$$\Ome...

Which of the following gates will give an output '1' for the given inputs? ...

For a common-emitter amplifier, the voltage gain is 40. Its input and output impedances are $$100 \Omega$$ and $$400 \Omega$$, respectively. The power...

Choose the correct statement. In semiconductors valance band and conduction band

A logic gate which gives output 'HIGH' only when its two input terminals are at different logic levels with respect to each other is

Choose the FALSE statement from the following.

In an n-p-n transistor 200 electrons enter the emitter in 10$$^{-8}$$ second. If 1% electrons are lost in the base, then the current that enters the e...

Combination of NAND gates is shown in the figure. It is equivalent to ...

In an ideal junction diode, the current flowing through PQ is ...

LED is manufactured using zinc selenide then it emits.

In a pure silicon, number of electrons and holes per unit volume are $$1.6 \times 10^{16} \mathrm{~m}^{-3}$$. If silicon is doped with Boron in a way ...

For a transitor, $$\frac{1}{\alpha_{\mathrm{DC}}}-\frac{1}{\beta_{\mathrm{DC}}}$$ is equal to [ $$\alpha_{\mathrm{DC}}$$ and $$\beta_{\mathrm{DC}}$$ a...

The current in the following circuit is ...

The output of an 'OR' gate is 'one'

In the case of insulators, a band gap and conduction band is respectively

A rectifier is used to

Two different logic gates moving output '0' for the inputs (0, 1) and then for (1, 0) are

The frequency of a given a.c. signal is 'N' Hz. When it is connected to a half wave rectifier, the number of output pulses given by the rectifier in 1...

Silicon and copper are cooled from 300 K to 100 K, the specific resistance (resistivity)

A transistor having $\alpha=0.8$ is connected in common emitter configuration. When the base current changes by 6 mA , then the change in collector cu...

In an intrinsic semiconductor, at an ordinary temperature, the correct relation between the number of electrons per unit volume $n_e$ and number of ho...

$$A$$ transistor has a voltage gain $$A$$. If the amount $$\beta A$$ of its output is applied to the input of the transistor, then the transistor beco...

At absolute zero temperature, pure silicon behaves as

In common emitter amplifier, input resistance is $$1000 \Omega$$, peak value of input signal voltage is $$5 \mathrm{~mV}$$ and $$\beta=60$$. The peak ...

When a small amount of impurity atoms are added to a semiconductor, then generally its resistivity

$V-I$ characterstics of LED is shown correctly by graph

Which of the following regions of a transistors are, respectively, heavily dopped and lightly dopped?

In case of $p$-n junction diode, the width of depletion region is

In the study of transistor as an amplifier, the ratio of collector current to emitter current is 0.98 then the ratio of collector current to base curr...

Assuming that the junction diode is ideal, the current in the arrangement shown in figure is ...

. For a transistor, the current ratio ' $\beta_{d c}$ ' is defined as the ratio of