# What is the power factor of purely resistive circuit?

What is the power factor of purely resistive circuit.

Power factor of purely resistive circuit is unity.

Unity that is 1

## Related questions

Description : In a pure resistive circuit, the average power Pavg is ______ the peak power Pmax. (1) Double (2) One-half of (3) One-fourth (4) Equal to

Last Answer : In a pure resistive circuit, the average power Pavg is One-half of the peak power Pmax.

Description : In a purely inductive circuit?

Last Answer : In a purely inductive circuit actual power is zero.

Description : In a pure resistive circuit?

Last Answer : In a pure resistive circuit current is in phase with the voltage.

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

Last 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.

Description : The power factor of a D.C. circuit is always?

Last Answer : The power factor of a D.C. circuit is always unity.

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?

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

Last 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.

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

Last 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?

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

Description : Give the circuit analysis of current source inverter with resistive load. What are the main difference between voltage source inverter and current source inverter?

Last Answer : Current source inverter (CSI): In current source inverter, the output current is independent of load. The input current of current source inverter is constant. Current source converter converts DC input current to ... are connected in parallel. In CSI diodes are connected in series.

Description : At ______ frequencies the parallel R-L circuit behaves as purely resistive.

Last Answer : At very high frequencies the parallel R-L circuit behaves as purely resistive.

Description : A 3-phase voltage source inverter operates in 180° conduction mode with a star connected resistive load. If input dc voltage is 100 V, then the peak to peak output line voltage is :

Last Answer : A 3-phase voltage source inverter operates in 180° conduction mode with a star connected resistive load. If input dc voltage is 100 V, then the peak to peak output line voltage is : 200 V

Description : Single-phase Midpoint controlled rectifier with Resistive load

Last Answer : Single-phase Midpoint controlled rectifier with Resistive load:  1) During positive half cycle of AC supply, a is positive with respect to b , this makes T1 forward biased and T2 is reverse ... voltage reverses the polarity and T2 is turned off. The operation is as shown in waveforms.

Description : Why capacitors are used to improve power factor?

Last Answer :  Capacitors generate reactive power instead of that drawn from source which is required by inductive loads.so it reduce the reactive current which is drawn from source to be drawn from capacitor.This control in Electric bills cost.

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

Last 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 : State the significance of power factor.

Last Answer : Significance of power factor:-  1. Cosine of angle between voltage & current in a circuit is called power factor. 2. It is a measure of the real power in a circuit. 3. Inductive & ... KVA rating equipment 5. Greater conductor size 6. CosØ = R/Z  CosØ= Active Power/ Apparent Power

Description : The power factor of dielectric :  (A) is a function of temperature of the dielectric only (B) depends only on voltage stress to which the dielectric is stressed (C) always constant (D) both (A) and (B)

Last Answer : The power factor of dielectric :  (A) is a function of temperature of the dielectric only (B) depends only on voltage stress to which the dielectric is stressed (C) always constant (D) both (A) and (B)

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

Last 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

Description : The ratio of active power to apparent power is known as____ factor.

Last Answer : The ratio of active power to apparent power is known as power factor.

Description : Power factor of electric bulb is?

Last Answer : Power factor of electric bulb is unity.

Description : Power factor of the system is kept high?

Last Answer : Power factor of the system is kept high to reduce line losses, to maximise the utilization of the capacities of generators, lines and transformers, to reduce voltage regulation of the line.

Description : Capacitors for power factor correction are rated in?

Last Answer : Capacitors for power factor correction are rated in kVAR.

Description : Poor power factor?

Last Answer : Poor power factor reduces load handling capability of electrical system, results in more power losses in the electrical system, overloads alternators, transformers and distribution lines, results in more voltage drop in the line.

Description : What is meant by Power factor?

Last Answer : Ans. Power factor means ratio of true power to apparent power. It is cosine of phase angle between voltage and current. Its value is 1 for Unity P.F. Loads, 0 to 1 lagging for inductive loads and o to 1 leading for capacitive loads.

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

Last 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 : Discuss how power factor tariff results into energy conservation.

Last Answer : Power factor tariff results into energy conservation: i) Applying incentives and penalties according to power factor is an effective way, which enables consumer to improve power factor so that he can ... finally leads to reduction in the current drawn by the load and helps for energy conservation.

Description : Draw and explain bulk correction method for power factor & control.

Last Answer : Bulk correction method for power factor & control: i) Here individual starter controls the capacitors located at distribution panel. ii) Centralized compensation is employed in large industrial plants where many ... capacitor units in steps to maintain P.F. more than preset limit (0.95).

Description : State the incentives and penalties related with power factor tariff.

Last Answer : Incentives and penalties related with power factor tariff: In addition to basic tariff (Maximum Demand Tariff / KVA Maximum Demand Tariff / Load factor tariff) the tariff in which P.F. of ... industrial consumer/H.T/ commercial consumers with contract demand above 80 kw/ 100Kva/107 hp consumer.

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

Description : Power station having Load factor = 70%, capacity factor = 50%, used factor = 60%, maximum demand = 20MW then annual energy production is  (1) 122.8 GWh (2) 198.55 GWh (3) 128.2 GWh (4) 188.82 GWh

Last Answer : Power station having Load factor = 70%, capacity factor = 50%, used factor = 60%, maximum demand = 20MW then annual energy production is 122.8 GWh

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

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

Description : The benefit of power factor correction in a power system is (A) lower power consumption (B) increased demand charge (C) reduced load carrying capabilities in existing lines (D) reduced voltage profile

Last Answer : The benefit of power factor correction in a power system is lower power consumption

Description : The power factor angle and torque angle of a salient pole synchronous generator drawing a current of 1.0 pu from a lagging load are 45o and 15o, respectively. The direct axis and quadrature axis currents, respectively, are (A) 0.5 pu ... pu, 0.5 pu (C) 0.707 pu, 0.707 pu (D) 0.5 pu, 0.5 pu

Last Answer : The power factor angle and torque angle of a salient pole synchronous generator drawing a current of 1.0 pu from a lagging load are 45o and 15o, respectively. The direct axis and quadrature axis currents, respectively, are 0.866 pu, 0.5 pu

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

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

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

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

Last Answer : A power factor meter has one current circuit and two pressure circuits.

Last Answer : In a low power factor wattmeter the compensating coil is connected in series with pressure coil.

Last Answer : In a low power factor wattmeter the pressure coil is connected to the load side of the current coil.

Last Answer : When a D.C. series motor is connected to A.C. supply, the power factor will be low because of high inductance of field and armature circuits.

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

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

Last 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.

Last Answer : The standard full-load power factor ratings for synchronous motors are unity or 0.8 leading.

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

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

Last Answer : In a distribution system, in order to improve power factor, the synchronous capacitors are installed at the receiving end.

Last Answer : For a consumer the most economical power factor is generally 0.95 lagging .

Last Answer : The primary reason for low power factor is supply system is due to installation of induction motors.

Last Answer : For high value of diversity factor, a power station of given installed capacity will be in a position to supply more number of consumers.