No load current in a transformer:

No load current in a transformer: (A) lags the applied voltage by 90° (B) lags the applied voltage by somewhat less than 90° (C) leads the applied voltage by 90° (D) leads the applied voltage by somewhat less than 90°
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Answer :

No load current in a transformer: lags the applied voltage by somewhat less than 90° 

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Related questions

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Description : What is the no-load current of transformer ?

Last Answer : The small amount of current flowing in the primary winding in the no-load condition of the transformer is called no-load current.

How much is the no load current of transformer?

Description : How much is the no load current of transformer?

Last Answer : No load curent of transformer is 3 to 5% of rated current in transformer.

What are two components of no load current in transformer?

Description : What are two components of no load current in transformer?

Last Answer : i) IM (Magnetizing/reactive /wattless) current. It magnetizes core ii) Iw (Coreloss/ active/wattful ) current. It supplies hysteresis and eddy current loss and negligible I² R loss.

What are the functions of no-load current in a transformer ?

Description : What are the functions of no-load current in a transformer ?

Last Answer : No-load current produces flux and supplies iron loss and copper loss on no-load.

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62)The no-load current drawn by transformer is usually........percent of the full-load current? A. 0.2 to 0.5 % B. 2 to 5% C. 12 to 15 % D. 20 to 30 %

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Last Answer : B) 2 to 5%

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No load current in a transformer: (A) lags the applied voltage by 90° (B) lags the applied voltage by somewhat less than 90° (C) leads the applied voltage by 90° (D) leads the applied voltage by somewhat less than 90°

Description : No load current in a transformer: (A) lags the applied voltage by 90° (B) lags the applied voltage by somewhat less than 90° (C) leads the applied voltage by 90° (D) leads the applied voltage by somewhat less than 90°

Last Answer : Ans: B The primary input current under no load conditions has to supply (i) iron losses in the core i.e hysteresis loss and eddy current loss (ii) a very small amount of Cu loss in the primary (there being no Cu loss in secondary as it is open)

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The no-load current drawn by transformer is usually what per cent of the full-load current ?

Description :  The no-load current drawn by transformer is usually what per cent of the full-load current ?

Last Answer : 5 to 8 percentage of full load current

No-load current in a transformer?

Last Answer : No-load current in a transformer lags behind the voltage by about 75°.

The no load current in a transformer lags behind the applied voltage by an angle of about?

Last Answer : The no load current in a transformer lags behind the applied voltage by an angle of about 75°.

No-load current of a transformer has?

Last Answer : No-load current of a transformer has small magnitude and low power factor.

In a three phase transformer, if the primary side is connected in star and secondary side is connected in...

Description : In a three phase transformer, if the primary side is connected in star and secondary side is connected in delta, the angle difference between phase voltage in the two cases will be: (A) delta side will lag by -30° ... will lag by -30° (C) delta side will lead by 30° (D) star side will lead by -30°

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Last Answer : The efficiency of a transformer is mainly dependent on: core losses

If a 220/440 V, 50 Hz, 5 KVA, single-phase transformer operates on 220V, 40Hz supply with secondary winding...

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Description : The no load speed of a d.c. shunt motor is 1140 rpm. At full load, the armature reaction weakens the main flux by 5% whereas the armature circuit voltage drops by 10%. The motor full load speed in rpm will be: (A) 1080 (B) 1203 (C) 1000 (D) 1200

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A load with an impedance of 440 ohms is connected across the secondary of the transformer illustrated. If the input voltage is 110 VAC and the step-up ratio is 10 to 1, what will be the primary current? EL-0055 A. 2.5 amps B. 25 amps C. 250 amps D. current cannot be determined with information given

Description : A load with an impedance of 440 ohms is connected across the secondary of the transformer illustrated. If the input voltage is 110 VAC and the step-up ratio is 10 to 1, what will be the primary current? EL-0055 A. 2.5 amps B. 25 amps C. 250 amps D. current cannot be determined with information given

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A load is connected to the secondary of the transformer illustrated and the current through the load is 10 amps. If the step-up ratio is 10 to 1 and the input voltage is 110 VAC, what will be the current flow through the primary? EL-0055 A. 1 amp B. 10 amps C. 100 amps D. 1000 amps

Description : A load is connected to the secondary of the transformer illustrated and the current through the load is 10 amps. If the step-up ratio is 10 to 1 and the input voltage is 110 VAC, what will be the current flow through the primary? EL-0055 A. 1 amp B. 10 amps C. 100 amps D. 1000 amps

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During No load why the power factor of the transformer is very low ?

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During No load why the power factor of the transformer is very low ?

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Description : A single-phase transformer has no-load loss of 64 W, as obtained from an open circuit test. When a short-circuit test is performed on it with 90% of the rated currents flowing in its both LV and HV windings, ... .0% of the rated current (C) 80.0% of the rated current (D) 88.8% of the rated current

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In an actual transformer the iron loss remains practically constant from no load to full load because?

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Last Answer : In an actual transformer the iron loss remains practically constant from no load to full load because core flux remains practically constant.

A no-load test is performed on a transformer to determine?

Description : A no-load test is performed on a transformer to determine?

Last Answer : A no-load test is performed on a transformer to determine magnetizing current and loss.

in open circuit or no load test of transformer which side is low voltage side and which side is high voltage side?

Last Answer : Primary side is low voltage side and secondary side is high voltage side.

The torque, in a_______ is proportional to the square of the armature current.

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The eddy current loss in an AC motor is 100 watts at 50 Hz. Its losses at 100 Hz will be:

Description : The eddy current loss in an AC motor is 100 watts at 50 Hz. Its losses at 100 Hz will be: (A) 25 watts (B) 59 watts (C) 100 watts (D) 400 watts

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The line trap unit employed in carrier current relaying method offers:

Description : The line trap unit employed in carrier current relaying method offers: (A) high impedance to 50 Hz power frequency signal (B) high impedance to carrier frequency signal (C) low impedance to ... signal (D) high impedance to 50 Hz power frequency signal and high impedance to carrier frequency signal

Last Answer : The line trap unit employed in carrier current relaying method offers: high impedance to carrier frequency signal 

A transformer has negative voltage regulation when its load power factor is- (a) Zero (b) Unity (c) Leading (d) Lagging

Description : A transformer has negative voltage regulation when its load power factor is- (a) Zero (b) Unity (c) Leading (d) Lagging

Last Answer : Ans: C

73 The full load copper loss of a transformer is 1600W. At half-load the copper loss will be A. 6400W B. 1600W C. 800W D. 400W

Description : 73 The full load copper loss of a transformer is 1600W. At half-load the copper loss will be A. 6400W B. 1600W C. 800W D. 400W

Last Answer : D. 400W

51 A transformer has negative voltage regulation when its load power factor is A. Zero B. Unity C. Leading D. Lagging

Description : 51 A transformer has negative voltage regulation when its load power factor is A. Zero B. Unity C. Leading D. Lagging

Last Answer : C. leading

6 In a two winding transformer, the primary and secondary induced emf E1 & E2 are always A. equal in magnitude B. anti phase with each other C. in phase with each other D. determined by load on transformer secondary

Description : 6 In a two winding transformer, the primary and secondary induced emf E1 & E2 are always A. equal in magnitude B. anti phase with each other C. in phase with each other D. determined by load on transformer secondary

Last Answer : C. In phase with each other

[23] Transformers are rated in KVA instead of KW because A. load power factor is often not known B. KVA is fixed whereas KW depends on load power factor C. Total transformer loss depends on volt ampere D. It has become customary

Description : [23] Transformers are rated in KVA instead of KW because A. load power factor is often not known B. KVA is fixed whereas KW depends on load power factor C. Total transformer loss depends on volt ampere D. It has become customary

Last Answer : C. Total transformer loss depends on volt ampere

5 The efficiency of a transformer is maximum when A. It runs at half full load B. it runs at full load C. its Cu loss equal iron loss D. it runs over load

Description : 5 The efficiency of a transformer is maximum when A. It runs at half full load B. it runs at full load C. its Cu loss equal iron loss D. it runs over load

Last Answer : C. Its cu loss equal iron loss

10] The main reason for generation of harmonics in a transformer could be A. Fluctuating load B. Poor insulation C. Mechanical vibrations D. Saturation of core

Description : 10] The main reason for generation of harmonics in a transformer could be A. Fluctuating load B. Poor insulation C. Mechanical vibrations D. Saturation of core

Last Answer : D) saturation of core

A two-winding single phase transformer has a voltage regulation of 4.5% at full-load and unity power-factor. At full-load and 0.80 power-factor lagging load the voltage regulation will be (A) 4.5%. (B) less than 4.5%. (C) more than 4.5%. (D) 4.5% or more than 4.5%.

Description : A two-winding single phase transformer has a voltage regulation of 4.5% at full-load and unity power-factor. At full-load and 0.80 power-factor lagging load the voltage regulation will be (A) 4.5%. (B) less than 4.5%. (C) more than 4.5%. (D) 4.5% or more than 4.5%.

Last Answer : (C) more than 4.5%.