Junction Transistor

An n-p-n transistor can be considered to be equivalent to two diodes connected. Which one of the following figure is correct?

In a transistor, comparing the doping of emitter, base and collector, the part which is heavily doped and that which is lightly doped are respectively

For a transistor, the current ratio $\alpha_{DC} = \frac{69}{70}$. The current gain $\beta_{DC}$ is

If transistor having $\alpha = 0.9$, is used in CE configuration, then for a change of $0.4$ mA in base current, what will be the change in collector current?

In transistor amplifier, base emitter junction is forward biased and collector base junction is reversed biased. The current gain is

The current gain in the common emitter mode of a transistor is $10$. The input impedance is $20\,k\Omega$ and load resistance $100\,k\Omega$. The power gain is

$\beta, R_L$ and $r$ are the a.c. current gain, load resistance and the input resistance of a transistor respectively in common emitter configuration, the voltage gain and the power gain are respectively

In common emitter amplifier, using output resistance $5000\,\Omega$ and input resistance $2000\,\Omega$, if the peak value of input signal voltage is $10$ mV and $\beta = 50$, then peak value of output voltage is

In a common emitter transistor amplifier, AC current gain is $65$, the load resistance is $5400\,\Omega$ and input resistance of the transistor is $450\,\Omega$. The voltage gain is

In common emitter configuration of transistor amplifier, $r_i, R_L$ and $\beta$ represent the input resistance, load resistance and the a.c. current gain respectively. The voltage gain $A_V$ and power gain $A_P$ are represented in magnitude respectively by

In an n-p-n transistor the collector current is $9$ mA. If $90\%$ of the electrons from the emitter reach the collector then

In an NPN transistor, the collector current is 28 mA. If 80% electrons reach the collector, its base current in mA is

In common emitter mode of transistor, the d.c. current gain is 20, the emitter current is 7 mA. The collector current is

In common emitter mode of transistor, the d.c. current gain is $20$, the emitter current is $7$ mA. The collector current is

In a transistor 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$\Omega$ and voltage gain is 75, the load resistance used in the circuit is

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$\Omega$ and voltage gain is $75$, the load resistance used in the circuit is

In common emitter transistor amplifier, the output resistance is $500$ k$\Omega$ and the current gain $\beta = 50$. If power gain of amplifier is $5 \times 10^{6}$, what is the input resistance?

In an n-p-n transistor in common emitter configuration when $V_{BE}$ is increased by small amount then

For a transistor, $\alpha_\text{dc}$ and $\beta_\text{dc}$ are the current ratios, then the value of $\frac{\beta_\text{dc} - \alpha_\text{dc}}{\alpha_\text{dc} \times \beta_\text{dc}}$

In a common emitter transistor amplifier circuit, the current gain $\alpha = 0.8$. If the base current changes by $3\,\mu\text{A}$ then the collector current changes by

In the case of common emitter transistor amplifier, the ratio of collector current to emitter current is 0.96, then the current gain $(\beta)$ of the amplifier is

For a common emitter transistor, if $\frac{I_\text{C}}{I_\text{E}} = 0.95$, then the current gain is

In the case of constant ' $\alpha$ ' and ' $\beta$ ' of a transistor ( $\alpha$ and $\beta$ are current ratios)

In a common emitter transistor amplifier, the output voltage and input voltage have a phase difference of

In common emitter mode of a transistor, the current gain is 8. The input impedance is $25\text{ k}\Omega$ and load resistance is $75\text{ k}\Omega$. The power gain is

When an n-p-n junction transistor is used as an amplifier in common emitter mode,

In a transistor amplifier, AC current gain is 64, the load resistance is $5400\ \Omega$ and the input resistance of the transistor is $540\ \Omega$. The voltage gain is

In an n-p-n transistor amplifier, the collector current is 8 mA. If $80\%$ of the electrons from the emitter reach the collector, then ( $\alpha$ and $\beta$ are current ratios)

In an n-p-n transistor amplifier, the collector current is 9 mA. If $90\%$ of the electrons emitted reach the collector, then

In a common emitter transistor amplifier circuit, the input resistance is $1.8\text{ k}\Omega$ and output is obtained across a load resistance of $9\text{ k}\Omega$. The alternating current gain is 70. Corresponding to an a.c. input voltage of 6 mV, the output voltage will be

In a common emitter amplifier configuration, the current gain is 62. The collector resistance and input resistance are $5\text{ k}\Omega$ and $500\ \Omega$ respectively. If the input voltage is 0.01 V, the output voltage will be

In a transistor (common emitter configuration) the ratio of power gain to voltage gain is ( $\alpha$ and $\beta$ are current ratios)

An n-p-n transistor can be considered to be equivalent to two diodes connected. The correct figure out of the following is

For a transistor, current gain $(\beta) = 50$. To change the collector current by $350\,\mu\text{A}$, the base current should be changed by

The input signal given to C.E. amplifier having a voltage gain of 126 is $V_i = 2\cos\left(12t + \frac{\pi}{3}\right)$. The corresponding output signal will be

When n-p-n junction transistor is used as an amplifier in common emitter mode,

In common emitter transistor amplifier, load resistance is $6.5\text{ k}\Omega$ and an input resistance is $1.3\text{ k}\Omega$. If the current gain is 78, the voltage gain is

The collector supply voltage is 6 V and a voltage drop across a resistor of $600\ \Omega$ in the collector circuit is 0.6 V, in a circuit of transistor connected in common emitter mode. If the current gain is 20 then the base current is

In an NPN transistor $10^{10}$ electrons enter the emitter in $10^{-6}\text{ s}$ and $2\%$ electrons recombine with holes in base. The current ratios ' $\alpha$ ' and ' $\beta$ ' of a transistor are respectively (nearly)

The current amplification factor of a transistor is 50. The input resistance when used in common emitter mode is $1\text{ k}\Omega$. The peak value for an a.c. input voltage of 0.01 V peak is

Given below are two statements:

Statement I: In a typical transistor, all three regions emitter, base and collector have same doping level.

Statement II: In a transistor, collector is the thickest and base is the thinnest segment. In the light of the above statements, choose the most appropriate answer from the options given below.

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

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 $\text{I}_\text{E}$ are collector, base and emitter current respectively then $\left(\frac{1}{\alpha} - \frac{1}{\beta}\right)$ is equal to

In an n-p-n common emitter (CE) transistor the collector current changes from 5 $\text{mA}$ to $16\text{ mA}$ for the change in base current from $100\,\mu\text{A}$ and $200\,\mu\text{A}$, respectively. The current gain of transistor is __________.

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

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

The above figure shows the circuit symbol of a transistor. Select the correct statements given below:

(A) The transistor has two segments of p-type semiconductor separated by a segment of n-type semiconductor.

(B) The emitter is of moderate size and heavily doped.

(C) The central segment is thin and lightly doped.

(D) The emitter base junction is reverse biased in common emitter amplifier circuit.

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

For a given transistor amplifier circuit in $\text{CE}$ configuration $\mathrm{V}_{\mathrm{CC}} = 1\text{ V}, \mathrm{R}_{\mathrm{C}} = 1\text{ k}\Omega, \mathrm{R}_{\mathrm{b}} = 100\text{ k}\Omega$ and $\beta = 100$. Value of base current $\mathrm{I}_{\mathrm{b}}$ is

From the given transfer characteristic of a transistor in $\text{CE}$ configuration, the value of power gain of this configuration is $10^{x}$, for $\mathrm{R}_{\mathrm{B}} = 10\text{ k}\Omega$, and $\mathrm{R}_{\mathrm{C}} = 1\text{ k}\Omega$. The value of $x$ is __________.

For a constant collector-emitter voltage of $8\text{ V}$, the collector current of a transistor reached to the value of $6\text{ mA}$ from $4\text{ mA}$, whereas base current changed from $20\,\mu\text{A}$ to $25\,\mu\text{A}$ value. If transistor is in active state, small signal current gain (current amplification factor) will be:

For a transistor to act as a switch, it must be operated in

The positive feedback is required by an amplifier to act an oscillator. The feedback here means:

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: n-p-n transistor permits more current than a p-n-p transistor.

Reason R: Electrons have greater mobility as a charge carrier.

Choose the correct answer from the options given below:

The collector current in a common base amplifier using n-p-n transistor is 24 mA. If 80% of the electrons released by the emitter is accepted by the collector, then the base current is numerically:

An n.p.n transistor with current gain $\beta = 100$ in common emitter configuration is shown in figure. The output voltage of the amplifier will be

A transistor is used in an amplifier circuit in common emitter mode. If the base current changes by 100 $\mu$A, it brings a change of 10 mA in collector current. If the load resistance is 2 k$\Omega$ and input resistance is 1 k$\Omega$, the value of power gain is x $\times$ 104. The value of x is _____________.

A transistor is used in common-emitter mode in an amplifier circuit. When a signal of 10 mV is added to the base-emitter voltage, the base current changes by 10 $\mu$A and the collector current changes by 1.5 mA. The load resistance is 5 k$\Omega$. The voltage gain of the transistor will be _________.

The typical transfer characteristics of a transistor in CE configuration is shown in figure. A load resistor of $2\text{ k}\Omega$ is connected in the collector branch of the circuit used. The input resistance of the transistor is $0.50\text{ k}\Omega$. The voltage gain of the transistor is ______________.

In an experiment of CE configuration of n-p-n transistor, the transfer characteristics are observed as given in figure.

If the input resistance is 200 $\Omega$ and output resistance is 60 $\Omega$, the voltage gain in this experiment will be ____________.

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

For a transistor, $\frac{1}{\alpha_\text{DC}} - \frac{1}{\beta_\text{DC}}$ is equal to [ $\alpha_\text{DC}$ and $\beta_\text{DC}$ are current amplification factors]

For a transistor $\alpha$ and $\beta$ are given as $\alpha = \frac{I_C}{I_E}$ and $\beta = \frac{I_C}{I_B}$. Then the correct relation between $\alpha$ and $\beta$ will be:

The correct relation between $\alpha$ (ratio of collector current to emitter current) and $\beta$ (ratio of collector current to base current) of a transistor is:

If an emitter current is changed by 4 mA, the collector current changes by 3.5 mA. The value of $\beta$ will be:

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

For a transistor in CE mode to be used as an amplifier, it must be operated in:

Given below are two statements:

Statement I: PN junction diodes can be used to function as transistor, simply by connecting two diodes, back to back, which acts as the base terminal.

Statement II: In the study of transistor, the amplification factor $\beta$ indicates ratio of the collector current to the base current.

In the light of the above statements, choose the correct answer from the options given below.

In a CE transistor, a change of $8.0\text{ mA}$ in the emitter current produces a change of $7.8\text{ mA}$ in the collector current. What change in the base current is necessary to produce the same change in the collector current?

A transistor is connected in common emitter circuit configuration, the collector supply voltage is 10 V and the voltage drop across a resistor of 1000 $\Omega$ in the collector circuit is 0.6 V. If the current gain factor ($\beta$) is 24, then the base current is _____________ $\mu$A. (Round off to the Nearest Integer)

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$\Omega$ and voltage gain is 75, the load resistance used in the circuit is

An npn transistor operates as a common emitter amplifier with a power gain of 106. The input circuit resistance is 100$\Omega$ and the output load resistance is 10 K$\Omega$. The common emitter current gain '$\beta$' will be ________. (Round off to the Nearest Integer).

The typical output characteristics curve for a transistor working in the common-emitter configuration is shown in the figure.

The estimated current gain from the figure is __________.

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 emitter and the current amplification factor are respectively [e = 1.6 $\times$ 10 $^{-19}$ C]

A circuit is arranged as shown in figure. The output voltage V0 is equal to ................... V.

For transistor action, which of the following statements is correct?

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 current is

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

A n-p-n transistor is connected in common emitter configuration (see figure) in which collector voltage drop across load resistance $(800\ \Omega)$ connected to the collector circuit is $0.8\text{ V}$. The collector current is

The output characteristics of a transistor is shown in the figure.

When VCE is 10V and IC = 4.0 mA, then value of $\beta$ac is __________.

$A$ 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 becomes oscillator, when

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

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 current will be

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

An n-p-n transistor operates as a common emitter amplifier, with a power gain of 60 dB. The input circuit resistance is 100$\Omega$ and the output load resistance is 10 k$\Omega$. The common emitter current gain $\beta$ is:

An NPN transistor is used in common emitter configuration as an amplifier with 1 k$\Omega$ load resistance. Signal voltage of 10 mV is applied across the base-emitter. This produces a 3 mA change in the collector current and 15μA change in the base current of the amplifier. The input resistance and voltage gain are:

The transfer characteristic curve of a transistor, having input and output resistance 100 $\Omega$ and 100 k$\Omega$ respectively is shown in the figure. The voltage and power gain, are respectively:

In the figure, given that VBB supply can vary from 0 to 5.0 V, VCC = 5V, $\beta$dc = 200, RB = 100 k$\Omega$, RC = 1 k$\Omega$ and VBE = 1.0 V. The minimum base current and the input voltage at which the transistor will go to saturation, will be respectively:

A common emitter amplifier circuit, built using an npn transistor, is shown in the figure. Its dc current gain is 250, RC = 1k$\Omega$ and VCC = 10 V. What is the minimum base current for VCE to reach saturation?

In a common emitter configuration with suitable bias, it is given that $R_L$ is the load resistance and $R_{BE}$ is small signal dynamic resistance (input side). Then, voltage gain, current gain and power gain are given, respectively, by:

$\beta$ is current gain, $\mathrm{I}_B, \mathrm{I}_C$ and $\mathrm{I}_E$ are respectively base, collector and emitter currents.

In the circuit shown in the figure, the input voltage Vi is 20 V, VBE = 0 and VCE = 0. The values of IB, IC and $\beta$ are given by

In a common emitter amplifier circuit using an n-p-n transistor, the phase difference between the input and the output voltages will be:

The current gain of a common emitter amplifier is 69. If the emitter current is 7.0 mA, collector current is:

In a common emitter transistor amplifier the audio sgnal voltage across the collector is 3 V. The resistance of collector is 3 k$\Omega$. If current gain is 100 and the base resistance is 2 k$\Omega$, the voltage and power gain of the amplifier is

For a common emitter configuration, if $\alpha$ and $\beta$ have their usual meanings, the incorrect relationship between $\alpha$ and $\beta$ is:

For CE transistor amplifier, the audio signal voltage across the collector resistance of 2 k$\Omega$ is 4 V. If the current amplification factor of the transistor is 100 and the base resistance is 1 k$\Omega$, then the input signal voltage is

The ratio (R) of output resistance r0, and the input resistance ri in measurements of input and output characteristics of a transistor is typically in the range:

A npn transistor is connected in common emitter 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 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

A realistic graph depicting the variation of the reciprocal of input resistance in an input characteristics measurement in a common emitter transistor configuration is:

An unknown transistor needs to be identified as a npn or pnp type. A multimeter, with + ve and − ve terminals, is used to measure resistance between different terminals of transistor. If terminal 2 is the base of the transistor then which of the following is correct for a pnp transistor?

The input signal given to a CE amplifier having a voltage gain of 150 is Vi = 2cos(15t + $\frac{\pi}{3}$ ). The corresponding output signal will be

An n-p-n transistor has three leads A, B and C. Connecting B and C by moist fingers, A to the positive lead of an ammeter, and C to the negative lead of the ammeter, one finds large deflection. Then, A, B and C refer respectively to:

One way in which the operation of a n-p-n transistor differs from that of a p-n-p

In a common emitter (CE) amplifier having a voltage gain G, the transistor used has transconductance 0.03 mho and current gain 25. If the above transistor is replaced with another one with transconductance 0.02 mho and current gain 20, the voltage gain will be

Transfer characteristics [output voltage (V0) vs input voltage (Vi)] for a base biased transistor in CE configuration is as shown in the figure. For using transistor as a switch, it is used

The input resistance of a silicon transistor is 100 $\Omega$. Base current is changed by 40 $\mu$A which results in a change in collector current by 2 mA. This transistor is used as a common emitter amplifier with a load resistance of 4 k$\Omega$. The voltage gain of the amplifier is

In a CE transistor amplifier, the audio signal voltage across the collector resistance of 2 k$\Omega$ is 2 V. If the base resistance is 1 k$\Omega$ and the current amplification of the transistor is 100, the input signal voltage is

A transistor is operated in common emitter configuration at VC = 2 V such that a change in the base current from 100 $\mu$A to 300 $\mu$A produces a change in the collector current from 10 mA to 20 mA. The current gain is

For transistor action

(1) Base, emitter and collector regions should have similar size and doping concentrations. (2) The base region must be very thin and lightly doped.

(3) The emitter-base junction is forward biased and base-collector junction is reverse biased. (4) Both the emitter-base junction as well as the base-collector junction are forward biased. Which one of the following pairs of statements is correct?