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Correct answer is (d) High

Best explanation: One of the most significant difference between a normal amplifier and of a current gain with resistive LOAD circuit is its high power gain. The construction of a current gain with resistive load circuit are APPROXIMATELY SIMILAR to a normal amplifier, HOWEVER the resistive load provides high power gain.

Correct answer is (a) VB / VS

Explanation: The overall voltage gain in a simplified common emitter hybrid MODEL while considering RS is CALCULATED as RATIO of base voltage over the APPLIED external voltage. It is expressed as VB / VS. Where, VS is the external applied voltage on the amplifier.

The CORRECT choice is (b) Dependent on β

The EXPLANATION is: CE short circuit gain obtained with hybrid pi model is better for linear circuits as compared to self – bias circuits as it is dependent on β. Voltage divider bias circuits are HIGHLY predictable whereas self – bias circuits are independent of β. THEREFORE, for a CE short circuit gain obtained with hybrid pi model linear circuits are preferred.

The correct answer is (c) It is USED as a voltage SOURCE at INPUT port

To explain I would say: While CHECKING the hybrid-pi conductance in low frequency H-parameters equivalent network of a two-port network we see that the hybrid-pi conductance in low frequency H-parameters h12 is sued as a voltage source at the input port. While using Kirchhoff’s voltage law, the hybrid-pi conductance in low frequency H-parameters equations can be represented as a FIXED voltage source of h21 V2 .

Right answer is (d) hie

Easy EXPLANATION: The input resistance of a common emitter (CE) amplifier can be EXPRESSED in terms of hybrid PARAMETERS in the hybrid-pi CE transistor model. The input resistance is universally expressed as hie . This is ALSO the same for approximate as WELL as exact hybrid models.

Right choice is (c) h21 = I2 / I1

To ELABORATE: To CALCULATE the value of h21 high frequency T model, we short circuit the output terminal so the output voltage V2 equals zero. Hence the EQUATION for hybrid parameters BECOMES, I2 = h21I1 + 0. Therefore, h21 = I2 / I1.

Correct answer is (C) AV × AI

To explain I would say: The power gain in a simplified common emitter hybrid MODEL is calculated as the product of voltage gain and power gain. It is expressed as AV × AI . It can also be further simplified as AI^2 × RL / Ri , where RL is LOAD resistance and Riis input resistance.

The correct ANSWER is (c) Low

The explanation is: The construction of a CURRENT gain with resistive LOAD CIRCUIT are approximately similar to a normal amplifier. The low output IMPEDANCE is one of the most prominent differentiating feature of a current gain with resistive load amplifier circuit.

Right answer is (d) To provide steady current or voltage

To elaborate: The Q – point of a device is the direct current or voltage of a device when no input is applied. The alpha cutoff FREQUENCY is a part of the device with provides the steady current or voltage. It is designed by DETERMINING the necessary voltage and current levels ACROSS each RESISTOR.

Correct choice is (d) g22 = V2 / I2

For explanation I would say: The inverse hybrid-pi CONDUCTANCE in low FREQUENCY H-parameters g22 for a two-port network is calculated by short circuiting the output terminal. In this CASE, the current V1 is equal to zero. The parameter g22 is calculated by taking the ratio of output terminal VOLTAGE over output terminal current.

The correct OPTION is (d) 2.32V

The best I can explain: The voltage VB of a SIMPLIFIED CB short circuit current frequency response configuration can be calculated using VB = I × R2. Given, VCC = 12V and R1 = 25kΩ and R2 = 6kΩ:

I = VCC / R1 + R2 = 12 / (25 + 6) = 0.387mA

VB = I × R2 = 0.387mA × 6kΩ = 2.32V

Right choice is (d) LOW frequency

Easy explanation: Low frequency conditions are used to check the LINEAR ANALYSIS of TRANSISTOR models. This is because, under low frequency d-c conditions the value of emitter current is almost equal to the value of collector current.

Right answer is (b) Bias point

Explanation: The small signal parameters in a transistor circuit taking SOURCE RESISTANCE into ACCOUNT vary with RESPECT to the bias point in the linear analysis model. This occurs even in the linear region of the CHARACTERISTIC curve of the transistor.

The correct answer is (a) Linear region

For EXPLANATION I would say: The operating point of the quiescent operating point is in the linear region of the output of the characteristic CURVE. In this region the input variations are PROPORTIONAL to the output variations and are easy to DETERMINE.

Right choice is (c) FEEDBACK amplifier

Best explanation: The current gain with resistive load amplifier is ONE of the most noticeable feedback AMPLIFIERS. It provides a negative current feedback to the circuit. These type of amplifiers are usually used in the END stage or the last stage of a SERIES of amplifiers.

Right answer is (c) To obtain a CURRENT IE insensitive to α and VBE

To elaborate: The aim of having an alpha cutoff frequency is to maintain a STABLE current or voltage, REGARDLESS of other parameters changing. Hence, we need RE to GET a stable IE current. Without RE the VALUE of IE changes drastically with a small change in α.

Correct answer is (a) STEADY state relations

To EXPLAIN: The STATIC transistor curve of a transistor defines the steady state relations between the input and output current and voltages. They are calculated and plotted with the help of DC measurements and LINEAR analysis is PERFORMED.

Correct answer is (a) Emitter voltage increases therefore base voltage increases

The explanation: If the collector current IC is increased, the corresponding emitter current ALSO increases. Which in turn CAUSES the voltage across RE to increase. This in turn causes a proportional rise in the base voltage SINCE VB = VE + VBE .

Correct choice is (c) g21 = V2 / V1

To elaborate: The inverse hybrid-pi conductance in LOW FREQUENCY H-parameters g21 for a two-port network is calculated by open CIRCUITING the output terminal. In this case, the current I2 is equal to zero. The parameter g21 is calculated by taking the ratio of output terminal voltage over input terminal voltage. It is ALSO known as the open circuit voltage gain.

The correct option is (a) AI × IB / IS

Easy explanation: The current GAIN in a SIMPLIFIED common emitter hybrid model while considering RS is calculated as the product of current gain without external parameters and the ratio of BASE current and external applied current. It is expressed as AI × IB / IS . Where, IS is the external applied current on the AMPLIFIER.

Right answer is (B) hre × hfe × Ib × RL

For explanation I would say: The magnitude of voltage generated at emitter circuit of a common emitter (CE) amplifier can be expressed in terms of hybrid parameters in the hybrid-pi CE transistor model. The magnitude of voltage generated is equal to hre × hfe × Ib × RL where, RL is LOAD resistance and Ib is the base current.

The correct answer is (C) Current

To explain I WOULD say: The current GAIN with resistive load configuration is prominently known for its feedback amplifier qualities. It is a negative feedback network that provides a negative feedback of current to the circuit. It is generally used in the LAST STAGE of an amplifying network.

The correct option is (d) Impedance MATCHING

To EXPLAIN I would say: The high input impedance along with low output impedance MAKES the current gain with resistive load amplifier ideal for impedance matching. Along with that, its KEY characteristics INCLUDE a comparatively high current and power gain.

Correct choice is (a) True

For explanation: It is more practical to calculate the APPROXIMATE values of voltage and current gains instead of computing the exact values of a common emitter amplifier circuit. We use a simplified common emitter hybrid MODEL to OBTAIN these approximate values without reducing the ACCURACY.

Right answer is (b) Input resistance

Easy explanation: The parameter H11 can be calculated by SHORT circuiting the output port. By doing so, we can CALCULATE h11 = V1 / I1 . Since this gives h11 the units of volts/ampere or in other words ohms, it is also known as input resistance.

The correct choice is (a) G11 = I1 / V1

For explanation: The inverse hybrid-pi conductance in low frequency H-parameters g11 for a two-port network is CALCULATED by open circuiting the OUTPUT terminal. In this case, the current I2 is EQUAL to zero. The parameter g11 is calculated by taking the ratio of input terminal current over input terminal voltage.

Right ANSWER is (c) EXPONENTIAL increase

Easiest explanation: In a physical model of a CB short circuit current FREQUENCY response, the output characteristic curve first increases exponentially and then remains constant. In the saturation region of working the output characteristics show an exponential increase in the collector current with respect to collector base VOLTAGE.

Right CHOICE is (d) 2.5

Explanation: To find the hybrid parameter h12 in a high frequency T MODEL we use the below MENTIONED formula. Given values are V2 = 20V and V1 = 50V.

h21 = V1 / V2 = 50 / 20 = 2.5

Right choice is (b) Input resistance

The EXPLANATION is: The parameter h11 can be CALCULATED by short circuiting the output port. By doing so, we can calculate h11 = V1 / I1. SINCE this gives h11 the units of volts / ampere or in other WORDS ohms, it is also known as input resistance in a high frequency T model.