# What is the power amplifier?

What is the power amplifier?

## Related questions

Description : An amplifier has input power of 2 microwatts. The power gain of the amplifier is 60 dB. The output power will be

Answer : An amplifier has input power of 2 microwatts. The power gain of the amplifier is 60 dB. The output power will be 2 watts

Description : What type of biasing is used in CE amplifier?

Description : What do you mean by frequency response of an amplifier?

Description : What is the advantage of differential amplifier?

Description : What is the use of differential amplifier?

Description : What is the meaning of operational amplifier?

Description : How does an operational amplifier work?

Description : What is distortion in class B amplifier

Description : A differential amplifier has a differential gain of 28000 and CMRR is 60 dB. What will be the value of common mode gain? A) Ac = 0.125 B) Ac = 0.33 C) Ac = 3 D) Ac = 28

Answer : A differential amplifier has a differential gain of 28000 and CMRR is 60 dB. What will be the value of common mode gain? A) Ac = 0.125 B) Ac = 0.33 C) Ac = 3 D) Ac = 28

Description : The unity gain bandwidth of an inverting amplifier is 10 MHz What would be the bandwidth if the gain is increased to 10 V/V? A) 100 MHz B) 1 MHz C) 10 MHz D) 1 kHz

Answer : The unity gain bandwidth of an inverting amplifier is 10 MHz What would be the bandwidth if the gain is increased to 10 V/V? A) 100 MHz B) 1 MHz C) 10 MHz D) 1 kHz

Description : What is the efficiency of Class-B amplifier?  A) 68.50% B) 78.50% C) 88.50% D) 98.50%

Answer : What is the efficiency of Class-B amplifier?  A) 68.50% B) 78.50% C) 88.50% D) 98.50%

Description : What is a BJT amplifier?

Description : What is stability in an amplifier?

Description : working of class B push pull amplifier.

Answer : Circuit Diagram:- Operation:  In class B amplifier transistor conduct only for half cycle of input signal.One conduct in positive half cycle and other conducts in negative half ... Then output transformer joins these two halves and produces a full sine wave in the load resistor.

Description : Compare amplifier and oscillator.

Answer : Figure shows a block diagram of an amplifier and an oscillator.   An amplifier is a device, which produces an output signal with similar waveform as that of the input. ... is supplied. An oscillator does not require any external signal to start or maintain energy conversion process.

Description : role of tuned LC circuit in tuned amplifier.

Answer : In order to pick up and amplify the desired radio frequency signal, the resistive load in the audio amplifier is replaced by a tuned circuit (also called a parallel resonant circuit)as shown ... desired radio frequency signal. (ii)Amplification of the selected signal to a suitable voltage level.

Description :  applications of RC coupled amplifier

Answer : Applications of RC coupled amplifier: (i) Widely used as Voltage amplifiers. (ii) They are used in Public Address System. (iii) In Tape recorders. (iv) In stereo amplifiers (v) In T.V. V.C.R. and C.D. Players.

Description : characteristics of Hi-Fi amplifier system.

Answer : Characteristics of HI-FI amplifier: 1. Signal to noise ratio should be better than 50dB. 2. Frequency response should be flat within +-1dB. 3. Nonlinear distortion should not be more ... provided. 6. Environmental conditions should be such as to eliminate the external noise in listening room.

Description :  two stage amplifier and need of multistage amplifier.

Answer : Circuit diagram of two stage amplifier : Need of multistage amplifier: The output from a single stage amplifier is usually insufficient to drive an output device. So that ... to second amplifier.  To increase the overall gain of the amplifier multistage amplifier is needed.

Description : advantages and disadvantages of direct coupled amplifier over RC coupled amplifier.

Answer : Advantages:  Due to absence of coupling capacitors, the gain does not reduce on the lower frequency side.  This amplifier can amplify dc signals. Reduced cost and complexity due to absence of ...   The output waveform has a dc shift.  Poor frequency response at a higher frequency.

Description :  transformer coupled amplifier

Description : Single stage CE amplifier

Answer : Requirement(Necessity) of Multistage amplifier: -In many applications we required a high gain. But sometimes gain produced by an amplifier is not sufficient so to increase the gain, we ... necessity of multistage amplifier is for providing high gain. It is also required for high bandwidth.

Description : Give the different types of amplifier coupling.

Answer : 1. Resistance – capacitance (RC) coupling.  2. Inductance (LC) coupling.  3. Transformer coupling (TC)  4. Direct coupling (D.C.)

Description : State the need of multistage amplifier. Draw frequency response of R-C coupled amplifier.

Answer : The need of multistage amplifier The voltage (or power) gain, obtained from a single stage small signal amplifier, is limited. Therefore, it is not sufficient for all practical applications. Therefore, in ... to use a MULTISTAGE AMPLIFIER .  Frequency response of R-C coupled amplifier.

Description : Define gain and bandwidth of an amplifier.

Answer : Bandwidth  The range of frequency over which the voltage gain is equal to or greater than 70.7% of its maximum value Gain: The ratio of output parameter (voltage/ current /power) to the input parameter (voltage/ current /power) of an amplifier is known as gain. It is denoted by a letter A

Description : Draw diagram of class A push-pull amplifier and explain its operation.

Answer : Class A Push-pull Amplifier: The circuit diagram of class A push-pull amplifier is as shown in the fig.(a). Operation: The resistors R1 and R2 along with Vcc provide the dc biasing so as ... Vcc is applied to the collectors of transistors Q1 and Q2 through the centretapped output transformer.

Description : State the need of cascade amplifier and draw circuit diagram of 2-stage direct coupled amplifier.

Answer : Need:- The voltage (or power) gain, obtained from a single stage small signal amplifier, is limited. Therefore, it is not sufficient for all practical applications. Therefore, in order to obtain greater voltage and power gain, cascade amplifiers are used.

Description : Compare RC coupled, transformer coupled and direct coupled amplifier based on four points.

Answer : Parameter RC coupled Transformer coupled Direct coupled  Coupling element Resistor and capacitor Transformer No element Impedance matching Poor Excellent good Frequency ... Low frequency amplifier,opamp Size and cost small Large and bulky least

Description : List the advantages of RC coupled amplifier.

Answer : Advantages: 1. The frequency response is excellent 2. The circuit is very compact and extremely light 3. Cost is low because it employ resistors and capacitors which are cheap

Description : State the need of cascade amplifier.

Answer : Most systems a single transistor amplifier does not provide sufficient gain or bandwidth or will not have the correct input or output impedance matching. Hence cascade amplifier is use which consist more than one stages of amplification.

Description : Which one of the following is another name for common-collector amplifier?  A) Source follower B) Collector follower C) Base follower D) Emitter follower

Answer : Which one of the following is another name for common-collector amplifier?  A) Source follower B) Collector follower C) Base follower D) Emitter follower

Description : The voltage gains of the amplifier with and without feedback are 20 and 100 respectively. The percentage of negative feedback would be

Answer : The voltage gains of the amplifier with and without feedback are 20 and 100 respectively. The percentage of negative feedback would be 4%

Description : A differential amplifier has a differential gain of 20,000, CMRR : 80 dB. The common mode gain is given by

Answer : A differential amplifier has a differential gain of 20,000, CMRR : 80 dB. The common mode gain is given by 2

Description : An amplifier has a voltage gain of 120. To reduce distortion, 10% negative feedback is employed. The gain of the amplifier with feedback is  (1) 141 (2) 92.3 (3) 9.23 (4) 1.41

Answer : An amplifier has a voltage gain of 120. To reduce distortion, 10% negative feedback is employed. The gain of the amplifier with feedback is 9.23

Description : The voltage gain of a common -source JFET amplifier depends up on its  (1) Input impedance (2) Amplification factor (3) Dynamic drain resistance (4) Drain load resistance

Description : The gain of an ideal amplifier must be

Answer : The gain of an ideal amplifier must be infinity

Description : The effect of a finite gain of an operational amplifier used in an integrator is that (A) it would not integrate (B) the slope of the output will vary with time (C) the final value of the output voltage will reduce (D) there will be instability in the circuit

Answer : The effect of a finite gain of an operational amplifier used in an integrator is that there will be instability in the circuit

Answer : The voltage regulation in magnetic amplifier type voltage regulator is effected by varying the reactance.

Description : How can BJT be used as an amplifier?

Description : How does negative feedback reduces distortion in an amplifier?

Answer : ADC-Amplifier interface: In most data acquisition system analog to digital converter (ADC) is interfaced with the amplifier. There are different interface architectural schemes. Operational ... . The interaction between analog to digital converter and amplifier affects the system performance.

Answer : Active region of BJT act as amplifier.

Description : What is the value of capacitance required to improve power factor from 0.7 to 0.9. Given that: Real power = 50 W Vrms of the source = 120 Frequency = 50 Hz   #powerfactor

Description : What are the basic requirements of locating wind power plant ?

Answer : The basic requirements of locating wind power plant:  1) The site should be selected where winds are strong i.e. where pressure of wind is high and there is continuity. 2) Wind pressure ... the turbine which can affect the system's overall performance. 10)Possibility to connect to power grid.

Description : What are the criteria for selection of site for hydroelectric power plant?

Answer : Following Factors to be kept while site selecting for Hydro power plant:  1. It should be located where high rain fall occurs. 2. A large catchments area must be available to store water. 3. It ... 12. Cost of land should be less. 13. Skilled and unskilled man power should be available nearby.

Description : Options: A) WATT B) AMPERE C) VOLTS D) OHM

Description : What is the choice of size and number of generator units in interconnected power system?

Answer : Choice of Size and Number of Generating Units: 1. The size/rating and number of generating units in such way that they approximately match with the load curve as closely as possible. 2. In ... , if power plant is connected to grid system then generating unit of higher capacity can be installed.

Description : What is need of regulated power supply?

Answer : A regulated power supply is used to ensure that the output remains constant even if the input changes. But sometimes main supply voltage, load, and surrounding temperature keep changing and altering the ... power supply is needed that will accept an AC input and give a constant DC output.

Description : What is the Power Supply specification for 8085AH microprocessor? A) Single +5V supply with 10% voltage margins B) Dual +5V supply with 10% voltage margins C) Single +10V supply with 5% voltage margins D) Dual +5V supply with 5% voltage margins

Answer : What is the Power Supply specification for 8085AH microprocessor? A) Single +5V supply with 10% voltage margins B) Dual +5V supply with 10% voltage margins C) Single +10V supply with 5% voltage margins D) Dual +5V supply with 5% voltage margins

← Prev Question Next Question →