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If the supply frequency to the transformer is increased, the iron loss will?
asked
Mar 19, 2018
by
anonymous
supply
frequency
transformer
increased
iron
loss
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1
Answer
answered
Mar 19, 2018
by
anonymous
If the supply frequency to the transformer is increased, the iron loss will
increase.
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Related questions
asked
Mar 19, 2018
by
anonymous
In an actual transformer the iron loss remains practically constant from no load to full load because?
Last answer:
In an actual transformer the iron loss remains practically constant from no load to full load because core flux remains practically constant.
transformer
iron
loss
constant
load
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1
answer
asked
Mar 19, 2018
by
anonymous
Iron loss of a transformer can be measured by?
Last answer:
Iron loss of a transformer can be measured by low power factor wattmeter.
iron
loss
transformer
measured
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1
answer
asked
Apr 30, 2018
by
anonymous
At full -load of a transformer, the iron loss and copper loss are 3000 W and 4000 W respectively. Then total
At full -load of a transformer, the iron loss and copper loss are 3000 W and 4000 W respectively. Then total loss at maximum efficiency is : (A) 7000 W (B) 6000 W (C) 8000 W (D) 4000 W
Last answer:
At full -load of a transformer, the iron loss and copper loss are 3000 W and 4000 W respectively. Then total loss at maximum efficiency is : 6000 W
full-load
transformer
iron
loss
copper
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1
answer
asked
Mar 20, 2018
by
anonymous
If the synchronous motor, properly synchronised to the supply is running on no load and is having negligible loss then?
Last answer:
If the synchronous motor, properly synchronised to the supply is running on no load and is having negligible loss then the stator current will be zero.
synchronous
motor
synchronised
supply
running
load
negligible
loss
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1
answer
asked
Mar 19, 2018
by
anonymous
When secondary of a current transformer is open-circuited its iron core will be?
When secondary of a current transformer is open-circuited its iron core will be?
Last answer:
When secondary of a current transformer is open-circuited its iron core will be hot because of heavy iron losses taking place in it due to high flux density.
secondary
current
transformer
open-circuited
iron
core
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1
answer
asked
Mar 25, 2018
by
anonymous
A ferrite core has less eddy current loss than an iron core because?
A ferrite core has less eddy current loss than an iron core because?
Last answer:
A ferrite core has less eddy current loss than an iron core because ferrites have high hysteresis.
ferrite
core
less
eddy
current
loss
iron
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1
answer
asked
Mar 25, 2018
by
anonymous
The effective resistance of an iron-cored choke working on ordinary supply frequency...
The effective resistance of an iron-cored choke working on ordinary supply frequency is more than its true resistance because of?
Last answer:
The effective resistance of an iron-cored choke working on ordinary supply frequency is more than its true resistance because of iron loss in core.
effective
resistance
choke
working
ordinary
supply
frequency
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1
answer
asked
May 8, 2018
by
anonymous
What will happen if the primary of a transformer is connected to D.C. supply?
What will happen if the primary of a transformer is connected to D.C. supply? (A) Transformer will operate with low efficiency (B) Transformer will operate with high efficiency (C) No effect (D) Transformer may start to smoke and burn
Last answer:
What will happen if the primary of a transformer is connected to D.C. supply? (A) Transformer will operate with low efficiency (B) Transformer will operate with high efficiency (C) No effect (D) Transformer may start to smoke and burn
transformer
dc
supply
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1
answer
asked
Mar 19, 2018
by
anonymous
In a step-down transformer, there is a change of 15 A in the load current. This results in change of supply current of?
In a step-down transformer, there is a change of 15 A in the load current. This results in change of supply current of?
Last answer:
In a step-down transformer, there is a change of 15 A in the load current. This results in change of supply current of less than 15A.
step-down
transformer
load
current
change
supply
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1
answer
asked
Apr 28, 2018
by
anonymous
The time period of third harmonic of power supply frequency, in milliseconds, is
The time period of third harmonic of power supply frequency, in milliseconds, is (A) 20 (B) 3.33 (C) 6.66 (D) 60
Last answer:
The time period of third harmonic of power supply frequency, in milliseconds, is 6.66
time
period
third
harmonic
power
supply
frequency
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481
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1
answer
asked
Jun 18, 2018
by
anonymous
The SCR would be turned OFF by voltage reversal of applied anode-cathode ac supply frequency of
The SCR would be turned OFF by voltage reversal of applied anode-cathode ac supply frequency of A) 10 kHz B) 10 Hz C) 5 kHz D) 5 Hz
scr
turned
off
voltage
reversal
anode-cathode
ac
supply
frequency
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0
answers
asked
May 8, 2018
by
anonymous
What would happen if a power transformer designed for operation on 50 Hz (frequency) were connected to
What would happen if a power transformer designed for operation on 50 Hz (frequency) were connected to a 500 Hz (frequency) source of the same voltage: (A) Eddy Current and Hysteresis losses will be excessive (B) Current will be too much high (C) Transformer may start to smoke and burn (D) No effect
Last answer:
What would happen if a power transformer designed for operation on 50 Hz (frequency) were connected to a 500 Hz (frequency) source of the same voltage: (A) Eddy Current and Hysteresis losses will be ... will be too much high (C) Transformer may start to smoke and burn (D) No effect
power
transformer
designed
operation
frequency
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1
answer
asked
Jun 18, 2018
by
anonymous
An AC supply of 230 V is applied to a half-wave rectifier circuit through a transformer having primary to
An AC supply of 230 V is applied to a half-wave rectifier circuit through a transformer having primary to secondary turn’s ratio 12:1. The peak inverse voltage is A) 8.62 V B) 12 V C) 19.17 V D) 27.11 V
Last answer:
An AC supply of 230 V is applied to a half-wave rectifier circuit through a transformer having primary to secondary turn’s ratio 12:1. The peak inverse voltage is A) 8.62 V B) 12 V C) 19.17 V D) 27.11 V
ac
supply
half-wave
rectifier
circuit
transformer
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1
answer
asked
May 8, 2018
by
anonymous
A 40 kVA transformer has a core loss of 400 W and a full load copper loss of 800 W. The
A 40 kVA transformer has a core loss of 400 W and a full load copper loss of 800 W. The proportion of full load at maximum efficiency is
Last answer:
A 40 kVA transformer has a core loss of 400 W and a full load copper loss of 800 W. The proportion of full load at maximum efficiency is 0.707
kva
transformer
core
loss
full
load
copper
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1
answer
asked
Mar 14, 2018
by
anonymous
Why does a transformer only work with an AC supply?
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
transformer
only
work
ac
supply
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109
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3
answers
asked
Mar 18, 2018
by
anonymous
If the load of the normally excited synchronous motor is increased the power factor will?
If the load of the normally excited synchronous motor is increased the power factor will?
Last answer:
If the load of the normally excited synchronous motor is increased the power factor will become lagging.
load
normally
excited
synchronous
motor
increased
power
factor
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80
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1
answer
asked
Mar 20, 2018
by
anonymous
The maximum constant load torque under which a synchronous motor will pull into synchronism...
The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as?
Last answer:
The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as pull-in torque.
maximum
constant
load
torque
synchronous
motor
synchronism
rated
rotor
supply
voltage
frequency
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213
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1
answer
asked
Mar 20, 2018
by
anonymous
The maximum torque which a synchronous motor will develop at rest for any angular position of the rotor...
The maximum torque which a synchronous motor will develop at rest for any angular position of the rotor, at rated stator supply voltage and frequency, is known as?
maximum
torque
synchronous
motor
rated
stator
supply
voltage
frequency
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86
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0
answers
asked
Mar 19, 2018
by
anonymous
The full-load copper loss of a transformer is 1600 W At half-load, the copper loss will be?
Last answer:
The full-load copper loss of a trans¬former is 1600 W. At half-load, the copper loss will be 400 W.
transformer
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66
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1
answer
asked
Mar 20, 2018
by
anonymous
As the load is increased the speed of D.C. shunt motor will?
Last answer:
As the load is increased the speed of D.C. shunt motor will reduce slightly.
load
increased
speed
dc
shunt
motor
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105
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1
answer
asked
Mar 19, 2018
by
anonymous
The purpose of providing an iron core in a transformer is to?
Last answer:
The purpose of providing an iron core in a transformer is to decrease the reluctance of the magnetic path.
transformer
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83
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1
answer
asked
Mar 20, 2018
by
anonymous
The increased load during summer months is due to?
Last answer:
The increased load during summer months is due to increased use of fans and air conditioners.
increased
load
summer
months
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34
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1
answer
asked
Mar 19, 2018
by
anonymous
If a transformer is continuously operated the maximum temperature rise will occur in?
If a transformer is continuously operated the maximum temperature rise will occur in?
Last answer:
If a transformer is continuously operated the maximum temperature rise will occur in windings.
transformer
continuously
operated
maximum
temperature
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56
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1
answer
asked
Mar 20, 2018
by
anonymous
If a D.C. series motor is operated on A.C. supply, it will?
Last answer:
If a D.C. series motor is operated on A.C. supply, it will spark excessively, have poor efficiency, have poor power factor.
dc
series
motor
operated
ac
supply
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63
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1
answer
asked
Apr 30, 2018
by
anonymous
The eddy current loss in a dc generator is 400 W at 40 Hz frequency of reversal and constant flux density.
The eddy current loss in a dc generator is 400 W at 40 Hz frequency of reversal and constant flux density. When frequency is increased to 50 Hz., eddy current loss is : (A) 256 W (B) 320 W (C) 500 W (D) 625 W
Last answer:
The eddy current loss in a dc generator is 400 W at 40 Hz frequency of reversal and constant flux density. When frequency is increased to 50 Hz., eddy current loss is : 625 W
eddy
current
loss
dc
generator
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77
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1
answer
asked
Mar 19, 2018
by
anonymous
The purpose of providing iron core in a step-up transformer is?
Last answer:
The purpose of providing iron core in a step-up transformer is to decrease the magnitude of magnetizing current.
transformer
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279
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1
answer
asked
May 7, 2020
by
anonymous
Select insulating materials for following parts : (i) Insulation between heating element and base plate of electric iron. (ii) Insulation used over copper or aluminium conductor used for making coils. (iii) Transformer bushings. (iv) Insulation between transmission line and pole.
Select insulating materials for following parts : (i) Insulation between heating element and base plate of electric iron. (ii) Insulation used over copper or aluminium conductor used for making coils. (iii) Transformer bushings. (iv) Insulation between transmission line and pole.
Last answer:
Parts Insulating Materials Insulation between heating element and base plate of electric iron. Mica Insulation used over copper or aluminium conductor used for making coils. ... Transformer bushings Porcelain Insulation between transmission line and pole. Porcelain
heating
element
and
base
plate
of
electric
iron
ii
used
over
copper
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68
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1
answer
asked
Mar 19, 2018
by
anonymous
If a transformer is switched on to a voltage more than the rated voltage?
If a transformer is switched on to a voltage more than the rated voltage?
Last answer:
If a transformer is switched on to a voltage more than the rated voltage its power factor will deteriorate.
transformer
switched
voltage
rated
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70
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1
answer
asked
May 8, 2018
by
anonymous
A change of 4% in the supply voltage to an induction motor will produce a change of approximately
A change of 4% in the supply voltage to an induction motor will produce a change of approximately
Last answer:
A change of 4% in the supply voltage to an induction motor will produce a change of approximately 8% in the rotor torque
supply
voltage
induction
motor
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190
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1
answer
asked
Apr 29, 2018
by
anonymous
An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic
An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic field having a component along the axis will be (1) unaffected (2) decreased (3) increased (4) either decreased or increased depending on the direction of the DC field
Last answer:
An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic field having a component along the axis will be either decreased or increased depending on the direction of the DC field
unshielded
moving
iron
voltmeter
used
measure
voltage
ac
circuit
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259
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1
answer
asked
Apr 29, 2018
by
anonymous
The iron alloy, ALNICO is mainly used to make ________
The iron alloy, ALNICO is mainly used to make ________ A) Temporary magnets B) Permanent magnets C) Transmission lines D) None of these
Last answer:
The iron alloy, ALNICO is mainly used to make Permanent magnets
iron
alloy
alnico
used
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54
views
1
answer
asked
Mar 20, 2018
by
anonymous
The steady state stability of the power system can be increased by?
Last answer:
The steady state stability of the power system can be increased by connecting lines in parallel.
steady
state
stability
power
system
increased
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92
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1
answer
asked
Apr 29, 2018
by
anonymous
What happens to the voltage in the secondary when the frequency of the supply in the primary is decreased?
What happens to the voltage in the secondary when the frequency of the supply in the primary is decreased? A) It increases B) It decreases C) It remains the same D) Cannot say unless the actual percentage increase in the frequency is known
Last answer:
What happens to the voltage in the secondary when the frequency of the supply in the primary is decreased? A) It increases B) It decreases C) It remains the same D) Cannot say unless the actual percentage increase in the frequency is known
voltage
secondary
frequency
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73
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1
answer
asked
Mar 21, 2018
by
anonymous
If the current in a capacitor leads the voltage by 80°, the loss angle of the capacitor is?
Last answer:
If the current in a capacitor leads the voltage by 80°, the loss angle of the capacitor is 10°.
capacitor
leads
voltage
loss
angle
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104
views
1
answer
asked
Mar 20, 2018
by
anonymous
For high value of diversity factor, a power station of given installed capacity will be in a position to supply?
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.
high
value
diversity
factor
power
station
installed
capacity
position
supply
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96
views
1
answer
asked
Mar 25, 2018
by
anonymous
In AC. circuits, laminated iron is invariably used in order to?
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.
ac
circuits
laminated
iron
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75
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1
answer
asked
May 8, 2018
by
anonymous
Stability of a transmission line can be increased by
Stability of a transmission line can be increased by
Last answer:
Stability of a transmission line can be increased by Shunt capacitor, Series capacitor
stability
transmission
line
increased
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260
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1
answer
asked
Mar 19, 2018
by
anonymous
The core used in high frequency transformer is usually?
Last answer:
The core used in high frequency transformer is usually air core .
transformer
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49
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1
answer
asked
Mar 19, 2018
by
anonymous
When a given transformer is run at its rated voltage but reduced frequency, its?
Last answer:
When a given transformer is run at its rated voltage but reduced frequency, its core flux density is increased.
transformer
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76
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1
answer
asked
Mar 19, 2018
by
anonymous
A transformer cannot raise or lower the voltage of a D.C. supply because?
Last answer:
A transformer cannot raise or lower the voltage of a D.C. supply because Faraday's laws of electromagnetic induction are not valid since the rate of change of flux is zero.
transformer
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134
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1
answer
asked
Jun 17, 2018
by
anonymous
If the frequency of input voltage of a transformer is increased keeping the magnitude of voltage unchanged,
If the frequency of input voltage of a transformer is increased keeping the magnitude of voltage unchanged, then: A) both hysteresis loss and eddy current loss in the core will increase B) hysteresis loss will increase but eddy current loss will decrease C) hysteresis loss will decrease but eddy current loss will increase D) hysteresis loss will decrease but eddy current loss will remain unchanged
Last answer:
If the frequency of input voltage of a transformer is increased keeping the magnitude of voltage unchanged, then: hysteresis loss will decrease but eddy current loss will remain unchanged
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173
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1
answer
asked
Mar 19, 2018
by
anonymous
The size of a transformer core will depend on?
The size of a transformer core will depend on?
Last answer:
The size of a transformer core will depend on frequency and area of the core.
size
transformer
core
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64
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1
answer
asked
Jul 1, 2019
by
anonymous
Which is the best conductor: silver, carbon, or iron?
Which is the best conductor: silver, carbon, or iron?
Last answer:
Silver is the best conductor. Carbon is the semiconductor. Iron have less conductance as compared to silver.
which
is
the
best
conductor
silver
carbon
or
iron
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50
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1
answer
asked
Apr 28, 2018
by
anonymous
A transformer at 25 Hz develops 20 W hysteresis loss and 50 W eddy current loss. If the applied voltage and
A transformer at 25 Hz develops 20 W hysteresis loss and 50 W eddy current loss. If the applied voltage and frequency are doubled, the new core losses are (A) 140 W (B) 180 W (C) 240 W (D) 480 W
Last answer:
A transformer at 25 Hz develops 20 W hysteresis loss and 50 W eddy current loss. If the applied voltage and frequency are doubled, the new core losses are 240 W
transformer
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69
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1
answer
asked
Apr 30, 2018
by
anonymous
The inrush current of a transformer at no load is maximum if the supply voltage is switched on
The inrush current of a transformer at no load is maximum if the supply voltage is switched on (1) at peak voltage value (2) at zero voltage value (3) at half voltage value (4) at 0.866 time voltage value
Last answer:
At 0.866 time voltage value
inrush
current
transformer
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80
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2
answers
asked
Mar 19, 2018
by
anonymous
An ideal transformer will have maximum efficiency at a load such that?
Last answer:
An ideal transformer will have maximum efficiency at a load such that copper loss equal to iron loss.
ideal
transformer
maximum
efficiency
load
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96
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1
answer
asked
Mar 19, 2018
by
anonymous
For a transformer, operating at constant load current, maximum efficiency will occur at?
For a transformer, operating at constant load current, maximum efficiency will occur at?
Last answer:
For a transformer, operating at constant load current, maximum efficiency will occur at unity power factor.
transformer
operating
constant
load
current
maximum
efficiency
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89
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1
answer
asked
Mar 19, 2018
by
anonymous
For given applied voltage, with the increase in frequency of the applied voltage?
For given applied voltage, with the increase in frequency of the applied voltage?
Last answer:
For given applied voltage, with the increase in frequency of the applied voltage eddy current loss will remain unchanged.
voltage
increase
frequency
applied
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167
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1
answer
asked
Mar 25, 2018
by
anonymous
In a magnetic material hysteresis loss takes place primarily due to?
In a magnetic material hysteresis loss takes place primarily due to?
Last answer:
In a magnetic material hysteresis loss takes place primarily due to it high retentivity.
magnetic
material
hysteresis
loss
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167
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1
answer
asked
Feb 16, 2018
by
anonymous
Explain hysteresis loss, eddy current loss and skin effect limitations with reference to magnetic material.
Explain hysteresis loss, eddy current loss and skin effect limitations with reference to magnetic material.
Last answer:
Hysteresis loss: Hysteresis loss is a loss which occurs due to the friction of magnetic domain due to the change in magnetic field in ferromagnetic material like iron. Hysteresis loss causes power loss ... loss in transformer is given by, We=Kef2Kf2Bm2watts Skin effect limitations:
explain
hysteresis
loss
eddy
current
skin
effect
limitations
magnetic
material
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