The ac bypassing of RF by CF in a common emitter configuration :
(A) increases ac signal across emitter -base junction (B) decreases ac signal across emitter -base junction (C) decreases voltage amplification (D) stabilizes the Q -point
The ac bypassing of RF by CF in a common emitter configuration : increases ac signal across emitter -base junction
Description : Why common emitter configuration is commonly used?
Last Answer : Common emitter configuration is commonly used for amplifications because 1. The common emitter configuration (CE) provides maximum voltage and current gain and hence provides maximum power gain. The ... automatic impedance matching maximum power transfer will take place from one stage to other.
Description : If the base current of a BJT is 250 µA and emitter current is 15 mA, then the common base current gain will be A) 0.98 B) 0.41 C) 59 D) 55
Last Answer : If the base current of a BJT is 250 µA and emitter current is 15 mA, then the common base current gain will be 0.98
Description : Explain open emitter BJT drive circuit.
Last Answer : open emitter BJT drive circuit:
Description : Draw full bridge & half bridge configuration with common cathode.
Last Answer : Half Bridge Configuration: Full Bridge Configuration:
Description : How to Stop a Common Cold
Last Answer : How to Stop a Common Cold The common cold hits all of us, and the worst part about having a cold is knowing that, while you can treat it, there is no miracle cure and you will probably catch a ... seven day, or if you develop a fever of more than one hundred degrees, go to the doctor immediately.
Description : six most common multiples
Last Answer : six most common multiples
Description : Which is the most common type of fault?
Last Answer : Single phase to ground fault is the most common type of fault.
Description : What is the most common type of power plant?
Last Answer : Hydroelectric power plant.
Description : Alternating current (AC)
Last Answer : AC stands for Alternating Current meaning voltage or current that changes polarity or direction respectively over time. An Alternating Current (AC) is an electric current whose magnitude ... energy are known as alternators and are simpler construction than DC electromechanical generators.
Description : Why are DC motors used in trains and not AC motors ?
Last Answer : The reason is torque. torque is inversely proportional to speed..i.e when th knowe train comes to rest position to motion.. initial speed is zero..so it requires high starting torque for ... current will flow through field and armature coils then maximum torque is available at the intial condition.
Description : Why is AC considered more efficient than DC?
Last Answer : Ac is more efficient than dc because it is easy to maintain and change the voltage of ac for transmission and distribution purpose. Plant cost of ac transmission is much lower compared to dc transmission. When fault occurs it is easy to interrupt ac supply.
Description : Which is more dangerous AC or DC and why ?
Last Answer : Dc is more dangerous than Ac because in Ac the voltage will varies but in dc the constant voltage
Description : Why is AC better for long distance power transmission than DC ?
Last Answer : ac is more economical to transmit for long distances . wires can be made smaller by step up transformer .. since major cost are wires to transmit .. then at the end of distance step down transformer is used for commercial use.
Description : Why can't we store AC in batteries instead of DC ?
Last Answer : Because the direction of the current changes in AC electricity, you cannot directly store the power. Placing a capacitor in an AC circuit has no effect on the alternating flow of the electricity. The only ... is indirectly, by storing DC and then using a power inverter to convert the DC to AC.
Description : What is the conversion between. AC to AC ? DC to DC? AC to DC? DC to AC ?
Last Answer : 1.ac to ac is regulation 2.dc to dc is chopper 3.ac to dc is rectifier 4.dc to ac is inverter
Description : AC generator
Last Answer : A.C power can be generated as a single phase or as a balanced poly-phase system. However, it was found that 3-phase power generation at 50 Hz will be economical and most suitable. Present day three phase generators ... has uniform air gap (figure 2.1(b)) and used when speed is high.
Description : Define : i) Average value ii) RMS value of an AC Wave.
Last Answer : i) Average value: The average value is defined as the average of all instantaneous values during one alternation . That is, the ratio of the sum of all considered instantaneous values to the ... as produced by the alternating current when flowing through the same resistance for the same time.
Description : Is the power line voltage available in our homes a dc or an ac voltage?
Last Answer : The power line voltage available in our homes is AC. Mobile dwellings are the most commonly DC-supplied homes and even then they tend to include AC supply for heavier loads.
Description : AC Circuits with Resistance but No Reactance
Last Answer : AC Circuits with Resistance but No Reactance AC Circuits with Resistance but No Reactance Series resistances let two resistances R 1 and R 2 are connected in series as shows in figure and there ... voltage. Voltage V A is common to both the branch hence voltage V A is common reference.
Description : What is the need of polarity marking in polyphase AC circuits?
Last Answer : Need of Polarity Marking in Polyphase AC Circuits: i) Polarity marking of terminals provides reference polarity for better understanding of system, even if the polarity of ac voltage changes ... of current transformers in relay protection circuit and getting desired performance is very difficult.
Description : Explain how sinusoidal AC voltage is generated by using simple one loop generator.
Last Answer : An electric current produced by means of electrical machine is known as generator which converts mechanical energy into electrical energy. When conductor cuts the magnetic flux, emf induced in it. (Faraday' ... upon position of armature. The nature of emf is alternating as shown by the waveform.
Description : ‘PMMC instrument is not suitable to measure AC quantity’. State the reason.
Last Answer : The direction of force exerted on moving coil depends on the direction of current flowing through moving coil. If the direction of magnetic field is kept constant, it produces unidirectional torque if the current is ... on the coil in one cycle to zero. Hence the meter cannot read A.C. quantities.
Description : Distinguish between AC and DC.
Last Answer : Particulars Direct Current Alternating Current Definition It is the current whose magnitude and direction do not change with respect to time. It is the current whose ... system, electroplating, Battery charging, Traction. AC machines, Domestic and industrial supply.
Description : The main advantage of AC over DC is: (A) Conversion flexibility from one voltage level to other (B) AC can be easily converted into DC by using a rectifier (C) AC is easy to maintain & can be easily distributed at long distances (D) All of the above
Last Answer : Ac is easy to maintain and ac can be easily converted to dc by rectifier .There is no commutator for conversion in ac that's why ac machines are weight less and more efficiency.ac machines occupy less space than dc .
Description : Which of the following motors can run on both AC and DC? A) Universal motor B) Dual wattage motor C) Flexible motor D) All the above
Last Answer : Which of the following motors can run on both AC and DC? A) Universal motor B) Dual wattage motor C) Flexible motor D) All the above
Description : Total instantaneous power supplied by a 3-phase ac supply to a balanced R-L load is
Last Answer : Total instantaneous power supplied by a 3-phase ac supply to a balanced R-L load is constant
Description : A parallel AC. circuit in resonance will?
Last Answer : A parallel AC. circuit in resonance will have a high impedance.
Description : In AC. circuits, laminated iron is invariably used in order to?
Last Answer : In AC. circuits, laminated iron is invariably used in order to reduce eddy current loss.
Description : In an AC. circuit, a low value of kVAR compared with kW indicates?
Last Answer : In an AC. circuit, a low value of kVAR compared with kW indicates high power factor.
Description : Do cell phones use AC or DC current?
Last Answer : DC of course.
Description : Why does a transformer only work with an AC supply?
Last Answer : The transformer work depends on the induction as main principle ,for that AC is the right means
Description : Is current from a battery AC or DC?
Last Answer : The current from the battery is DC
Description : How does AC current change direction?
Last Answer : This is because the angle at which the magnetic fields cuts across a winding changes its poles thus current has to change dirention .
Description : What is the direction of an AC current?
Last Answer : The magnitude and direction of alternating current is changes with respect to time. So for half cycle it is positive and for next half cycle it is negative.
Description : What is the symbol for AC power?
Last Answer : If you need to measure alternating current in a circuit, different multimeters have different symbols to measure it (and the corresponding voltage), usually "ACA" and "ACV," or "A" and "V" with a squiggly line (~) next to or above them.
Description : Why do we use AC current in our homes?
Last Answer : We used it for cooking rice, For washing clothes and for lights in the house.
Description : Can you apply Thevenin's theorem in an AC circuit?
Last Answer : It can be applied to AC circuits
Last Answer : Igbt alone cant convert dc to ac. igbt half bridge or full bridge or three phase topology could be used to convert dc to ac. also igbt gates should be driven by microcontroller or pwm/spwm gate driving signals ... e4(-) and g4 c2e1 and c4e3 pins are AC output pins. its name is igbt inverter.
Description : are AC and DC resistances same?
Last Answer : Resistance is the ability of a circuit or element (which is called resistor) to oppose current. Examples of Resistors with the ability of high resistance are Wood, Air, Mica, Glass, Rubber, Tungsten ... constant. Therefore, only the original resistance of wire comes into play. they are not the same
Description : In AC.S.R. conductors, the insulation between aluminium and steel conductors is (a) insulin (b) bitumen (c) varnish (d) no insulation is required
Last Answer : (d) no insulation is required
Description : What is AC ?
Last Answer : Ans. It is the current which changes its magnitude and direction periodically.
Description : Explain working of static AC circuit breaker.
Last Answer : Static AC Circuit breaker: The circuit configuration of static AC circuit breaker using SCR is shown in the figure. When switch S' is closed, the SCRs T1 and T2 are fired in positive ... non-availability of gate current. Thus the maximum time delay for breaking the circuit is one half-cycle.
Description : State the modification to be done in dc series motor to work satisfactorily as ac series motor. State applications of ac series motor.
Last Answer : Modifications are necessary in a dc series motor so that it operates satisfactorily on ac supply. The modifications are as follows: 1) AC series motor is built with a few field turns as ... and grinders 5) High speed vacuum cleaners 6) Sewing machines 7) Food processors 8) Drilling machine
Description : Explain construction and working of AC servomotor.
Last Answer : Construction of AC Servo Motor: AC servo motor is mainly composed of a stator and a rotor. Laminated stator core is usually made of silicon steel. Two phase windings are placed in the stator slots at 90 degree ... on rotor. Due to the force or torque acting on the rotor, it is set in motion.
Description : Compare the AC and DC Arc lamps.
Last Answer : AC Arc Lamp DC Arc Lamp Cross section area of electrode is same Cross section area of electrode is positive rod is twice that of negative rod Series inductor is used for stability ... supply is used for DC arc lamp Luminous efficiency is less Luminous efficiency is high
Description : Explain working of AC circuit breaker using SCR with circuit diagram.
Last Answer : AC Circuit Breaker: The circuit configuration of static AC circuit breaker using SCR is shown in the figure. When switch S' is closed, the SCRs T1 and T2 are fired in positive ... to non-availability of gate current. Thus the maximum time delay for breaking the circuit is one half-cycle.
Description : operation of half wave rectifier type AC Voltmeter.
Last Answer : Half-wave Rectifier Voltmeter The d'Arsonval meter movement only responds to the average or dc value of the current through the moving coil. In order to measure alternating ... ) input voltage signal alternating signal needs to be rectified first by using diode rectifier to produce
Description : AC power plugs and sockets
Last Answer : .embed-container { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; } .embed-container iframe, .embed-container object, .embed-container embed { position: absolute; top: 0; left: 0; width: 100%; height: 100%; }
Description : AC adapter
Description : AC power
Last Answer : Ac power is in sinusoidal wave form .Alternating current pulsating sinusoidally that is positive half cycle and negative half cycle.