# In an alternator at lagging power factor the generated voltage per phase as compared to that at unity power factor?

In an alternator at lagging power factor the generated voltage per phase as compared to that at unity power factor?

In an alternator, at lagging power factor the generated voltage per phase as compared to that at unity power factor must be more than terminal voltage.

## Related questions

Description : At which power factor alternator is said to be overexcited?

Answer : At leading power factor alternator is said to be overexcited.

Description : The power factor of an alternator depends on?

Description : The input of an A.C. circuit having power factor of 0.8 lagging is 40 kVA The power drawn by the circuit is?

Answer : The input of an A.C. circuit having power factor of 0.8 lagging is 40 kVA The power drawn by the circuit is 32 kW.

Description : In a synchronous generator delivering lagging power factor load  (1) the excitation emf leads terminal voltage by the power angle (2) the excitation emf lags terminal voltage by the power angle (3) ... by the power factor angle (4) excitation emf lags the terminal voltage by the power factor angle

Answer : In a synchronous generator delivering lagging power factor load the excitation emf leads terminal voltage by the power angle

Answer : An alternator coupled to a hydraulic turbine runs at slow speed, as compared to others.

Description : The magnitude of various voltage drops that occur in an alternator depends on?

Answer : The magnitude of various voltage drops that occur in an alternator depends on load current.

Description : In alternator where the voltage drop occurs?

Answer : In alternator voltage drop occurs in armature resistance, leakage reactance, and armature reactance.

Answer : In a single phase power factor meter the phase difference between the currents in the two pressure coils is exactly 90°.

Description : With a neat sketch explain working of 1 phase dynamometer type power factor meter.

Answer : Working of 1 phase dynamometer type power factor meter : The current coil is connected in series with load. Two pressure coils marked as A and B are connected across the supply terminals ... becomes stationary and the pointer shows steady deflection corresponding to the power factor of the load.

Description : What is the power factor when a single phase watt meter operating on 200 V and 5 A for 5 hours makes 2016 revolutions and the meter constant in revolution is 420? A) 0.04 B) 1.04 C) 0.96 D) None of these

Answer : What is the power factor when a single phase watt meter operating on 200 V and 5 A for 5 hours makes 2016 revolutions and the meter constant in revolution is 420? A) 0.04 B) 1.04 C) 0.96 D) None of these

Answer : The power factor of a single phase load can be calculated if the instruments available are three ammeters or three voltmeters.

Answer : The two pressure coils of a single phase power factor meter have the same dimensions and the same number of turns.

Description : Explain the concept of lagging and leading phase angle by waveform.

Answer : i) Leading phase angle :  When two ac quantities of same frequency do not attain their respective zero or peak values simultaneously, then the quantities are said to be out-of-phase quantities. The ... Similarly, in the second diagram, the voltage is said to be lagging the current by  Φ.

Description : The load duration curve for unity load factor will be of  (1) Rectangular shape (2) Triangular shape (3) L -shape (4) I -shape

Description : The damping factor of a particular system is unity, the system response will be

Answer : The damping factor of a particular system is unity, the system response will be critically damped

Description : A transformer has negative voltage regulation when its load power factor is   (1) Zero (2) Unity (3) Leading (4) Lagging

Description : Minimum voltage regulation occurs when the power factor of the load is?

Description : Explain lagging quantity and leading quantity, explain this concept with voltage and current waveform

Answer : When two alternating quantities attain their respective zero or peak values simultaneously, the quantities are said to be in-phase quantities. When the quantities do not attain their respective zero or ... current is leading the voltage or the voltage is said to be lagging behind the current.

Description : For a balanced three phase star connected load for which line voltage is 230V and per phase resistance and reactance is 6 Ohm and 8 Ohm respectively. Calculate: 1) phase voltage 2) line current 3) power factor 4) total power absorbed

Description : 220kV three phase transmission line is 60 km long. The resistance is 15 Ohms per phase and the inductance is j 30 Ohms. 1- Calculate : voltage regulation, TL line power losses and efficiency when ... for 0.85, calculate zise of the required capacitor  and the same parameters which were in part 1

Description : A synchronous motor has better power factor as compared to that of an equivalent induction motor. This is mainly because?

Answer : A synchronous motor has better power factor as compared to that of an equivalent induction motor. This is mainly because stator supply is not required to produce magnetic field.

Description : Explain how sinusoidal AC voltage is generated by using simple one loop generator.

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 : State the types of radioactive waste generated in a nuclear power station. Explain the methods employed for their disposal.

Answer : Types of radioactive waste: The waste produced in nuclear power plant is in the form of solid, liquid & gases, 1. Solid Waste Disposal:-  Solid wastes removed from the reactor are very ... are measured. If it is safe then released to atmosphere at high level through large height chimney.

Answer : In a dynamometer 3-phase power factor meter, the planes of the two moving coils are at 120°.

Answer : An induction motor has relatively high power factor at near full load.

Description : Is the speed of alternator is directly proportional to frequency?

Answer : Yes, speed of alternator is directly proportional to frequency.

Answer : The power factor of a single-phase induction motor is usually lagging.

Description : State the effects of low power factor on efficiency and voltage regulation of short transmission lines.

Answer : i) Effect of Low power factor on efficiency:- When power factor of load reduces current drawn by transmission line increases so copper losses in transmission line increases, hence transmission ... increases, so voltage drop in transmission line increases so regulation increases. (Become Poor)

Description : State working principle of alternator. State the meaning self and separate excitation.

Answer : Working principle of alternator: When a conductor is moved in magnetic field or a magnetic field moved with respect to conductor, according to Faraday's law of electromagnetic induction, the conductor ... like battery or shaft-mounted exciter, then the excitation is said to be separate excitation.

Description : Explain the construction of alternator with neat diagram.

Answer : Diagram: Construction of three phase alternator: Construction wise, an alternator generally consists of field poles placed on the rotating fixture of the machine i.e. rotor as shown in the ... of rotor used in construction of alternator, 1. Salient pole type. 2. Cylindrical rotor type.

Description : The power consumed in a circuit element will be least when the phase difference between the current and voltage is?

Answer : The power consumed in a circuit element will be least when the phase difference between the current and voltage is 90°.

Description : The product of apparent power and cosine of the phase angle between circuit voltage and current is?

Answer : In parllpar reasonans RLC circuit the current is

Description : The power factor at resonance in R-L- C parallel circuit is?

Answer : since a rlc circuit at resonance behaves like a pure resistive circuit, i.e there is no phase difference between current and voltage, hence the power factor is unity.

Answer : For power factor correction, synchronous motors operate at no-load and greatly over-excited fields.

Description : At which time power factor of the induction motor is low?

Answer : The power factor of the inducction motor is low at the time of starting as compare to while the induction motor is running.

Description : Power factor of an inductive circuit is usually improved by connecting capacitor to it in?

Answer : Power factor of an inductive circuit is usually improved by connecting capacitor to it in parallel.

Description : Power factor of an electrical circuit is equal to?

Answer : Power factor of an electrical circuit is equal to R/Z, cosine of phase angle difference between current and voltage, kW/kVA.

Description : List at least two examples that show how static electricity can be generated.

Answer : Examples of how static electricity can be generated include combing your hair, walking across a carpeted room, or sliding two pieces of plastic across each other.

Description : An alternator is delivering rated current at rated voltage and 0.8 power-factor lagging. For delivering rated current at rated voltage and 0.8 poWer—factor leading, the required excitation will be:  (A) less  (B) more (C) more or less (D) the same

Answer : An alternator is delivering rated current at rated voltage and 0.8 power -factor lagging. For delivering rated current at rated voltage and 0.8 power -factor leading, the required excitation will be: more

Description : Briefly explain how the power factor of an inductive circuit can be improved.

Answer : As we know that power factor should be corrected to ensure that the current supplied is cost friendly. Meaning the power factor should be around one but not greater than one(0.8-0.9) in a ... an inductive circuit due to the inductive reactance which oppose the change of current in the ac circuit.

Answer : The power loss is an important factor for the design of transmission line.

Description : Explain the need and steps to conduct the reduced voltage running up test on the three phase induction motor.

Description : A single core cable is designed to work for a single phase system with a peak voltage of 220 kV. The maximum permissible stress in the dielectric is not to exceed 20 kV/mm. For economical size, the overall core diameter of the cable is (A) 28.2 mm (B) 26.4 mm (C) 24.4 mm (D) 22.0 mm

Answer : A single core cable is designed to work for a single phase system with a peak voltage of 220 kV. The maximum permissible stress in the dielectric is not to exceed 20 kV/mm. For economical size, the overall core diameter of the cable is 22.0 mm

Description : What is the frequency of an alternator which has 2 poles and makes 3600 revolutions per minute? A) 3600 HZ B) 60 Hz C) 120 Hz D) None of these

Answer : What is the frequency of an alternator which has 2 poles and makes 3600 revolutions per minute? A) 3600 HZ B) 60 Hz C) 120 Hz D) None of these

Description : What is the voltage in 3 phase line?

Answer : between 430 to 440 v

Description : Write the relation between phase and line current, phase and line voltage for Star connection.

Answer : Line voltage is equal to root three times of phase voltage and line and phase currents are equal in star connection

Description : What is line voltage and phase voltage? Draw balanced three phase star connected system. Show all the voltages and currents.

Description : Draw the waveform of three phase AC supply voltage.

Description : What is the difference between line and phase voltage?

Answer : Line voltage  is  voltage  between two  phases R &Y  (415 v)  while  phase  voltage  is  the  voltage  between  one  phase and  a neutral  B &  N   (240 v).

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