Last Answer : Transformer core is laminated to reduce Eddy current losses.
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112 views
1 answer
asked
Sep 30, 2017
by
anonymous

The main purpose of using core in a transformer is to (A) decrease iron losses (B) eliminate magnetic hysteresis (C) reduce reluctance of the common magnetic circuit (D) prevent eddy current loss
Last Answer : Reduce Relucatnce of the common magnetic circuit.
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2.0k views
2 answers
asked
Apr 28, 2018
by
anonymous

State any four characteristics of core type transformer.
Last Answer : Characteristics of core type transformer: i) It has one window. ii) It has one magnetic circuit. iii) Core surrounds the winding. iv) Average length of core is more. v) Area of cross ... Better cooling for winding. vii) Mechnical strength is comparatively less. viii) Repair and maintenance is easy.
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132 views
1 answer
asked
Jul 27, 2019
by
anonymous

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
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774 views
1 answer
asked
May 8, 2018
by
anonymous
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The core construction is like spokes of a wheel in following transformer: (A) Berry Type Transformer (B) Core Type Transformer (C) Shell Type Transformer (D) None of the above
Last Answer : The core construction is like spokes of a wheel in following transformer: Berry Type Transformer
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133 views
1 answer
asked
May 8, 2018
by
anonymous

The desirable properties of transformer core material are (1) low permeability and low hysteresis loss. (2) high permeability and high hysteresis loss. (3) high permeability and low hysteresis loss. (4) low permeability and hysteresis loss.
Last Answer : The desirable properties of transformer core material are high permeability and low hysteresis loss.
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231 views
1 answer
asked
May 1, 2018
by
anonymous

Last Answer : Material used for construction of transformer core is usually silicon steel.
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241 views
1 answer
asked
Mar 19, 2018
by
anonymous

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.
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165 views
1 answer
asked
Mar 19, 2018
by
anonymous

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.
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114 views
1 answer
asked
Mar 19, 2018
by
anonymous

Reduction in core losses and increase in permeability are obtained with transformer employing?
Last Answer : Reduction in core losses and increase in permeability are obtained with transformer employing core built-up of laminations of cold rolled grain oriented steel.
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615 views
1 answer
asked
Mar 19, 2018
by
anonymous
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Why poles of dc machine are laminated?
Last Answer : Poles of DC machines are laminated to reduce the eddy current losses in the poles.
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112 views
1 answer
asked
Apr 27, 2020
by
anonymous

Laminated cores, in electrical machines, are used to reduce?
Last Answer : Laminated cores, in electrical machines, are used to reduce eddy current loss.
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104 views
1 answer
asked
Mar 25, 2018
by
anonymous
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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.
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105 views
1 answer
asked
Mar 25, 2018
by
anonymous

How to Clean Laminated Floors ?
Last Answer : How to Clean Laminated Floors Laminated floors offer beauty and style just like hardwood or stone floors, but with much easier maintenance. Made with dense fibers and wood particles, the flooring material is ... indoors. Clean up spills as soon as possible for easier removal, and you're all set.
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2 views
1 answer
asked
May 9, 2021
by
anonymous

205 views
0 answers
asked
Mar 20, 2018
by
anonymous

Why is the armature of DC generator laminated?
Last Answer : The armature of DC generator is laminated to reduce eddy current losses.
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176 views
1 answer
asked
Mar 3, 2018
by
anonymous

8 The transformer core is laminated to A. Reduce the copper losses B. Reduce the core losses C. Reduce the eddy current losses D. None of the above
Last Answer : C. Reduce the eddy current losses
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26 views
1 answer

State the material used for making (1) Magnetic Core (2) Fuse element
Last Answer : The material used for making of: (1) Magnetic Core : Iron, cobalt, Nickel, CRGO, HRGO , silicon steel (2) Fuse Element: Tin- lead wire, Tinned copper wire
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209 views
1 answer
asked
May 7, 2020
by
anonymous

Core type transformers are popular in___________. (A) High voltage applications (B) Low voltage applications (C) All of the above (D) None of the above
Last Answer : Core type transformers are popular in High voltage applications
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96 views
1 answer
asked
May 8, 2018
by
anonymous

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
Last 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
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756 views
1 answer
asked
Apr 28, 2018
by
anonymous

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.
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382 views
1 answer
asked
Mar 25, 2018
by
anonymous

A single core lead sheathed cable with two dielectrics of permittivity 4 and 3, respectively, are subjected to same maximum stress. If the conductor diameter is 1.5 cm, the outer diameter of the first dielectric is (A) 1.125 cm (B) 1.5 cm (C ) 2 cm (D) 8 cm
Last Answer : A single core lead sheathed cable with two dielectrics of permittivity 4 and 3, respectively, are subjected to same maximum stress. If the conductor diameter is 1.5 cm, the outer diameter of the first dielectric is 2 cm
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171 views
1 answer
asked
Apr 28, 2018
by
anonymous

Last Answer : The armature core of a D.C. generator is usually made of silicon steel.
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153 views
1 answer
asked
Mar 20, 2018
by
anonymous

Last Answer : When a conductor carries more current on the surface as compared to core, it is due to skin effect.
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171 views
1 answer
asked
Mar 20, 2018
by
anonymous

In DC generators lamination core are generally made of?
Last Answer : In DC generators lamination core are generally made of silicon steel.
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257 views
1 answer
asked
Mar 3, 2018
by
anonymous

State the need of biasing of BJT.
Last Answer : Need of biasing: The basic need of transistor biasing is to keep the base-emitter (B-E) junction properly forward biased and the collector-emitter (C-E) junction properly reverse biased ... transistor biasing is necessary for normal and proper operation of transistor to be used for amplification.
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262 views
2 answers
asked
Sep 5, 2018
by
anonymous

What is regulator ? State its need.
Last Answer : A voltage regulator is a circuit or device designed to deliver a constant voltage at its output regardless of changes in ac supply voltage and load current. Need:- A voltage regulator is one ... unexpected result or damage one of the components in the circuit, hence voltage regulator is needed.
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68 views
1 answer
asked
Sep 5, 2018
by
anonymous

State the need of cascade amplifier.
Last Answer : Most systems a single transistor amplifier does not provide sufficient gain or bandwidth or will not have the correct input or output impedance matching. Hence cascade amplifier is use which consist more than one stages of amplification.
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78 views
1 answer
asked
Sep 4, 2018
by
anonymous

What is need of regulated power supply?
Last Answer : A regulated power supply is used to ensure that the output remains constant even if the input changes. But sometimes main supply voltage, load, and surrounding temperature keep changing and altering the ... power supply is needed that will accept an AC input and give a constant DC output.
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136 views
3 answers
asked
Sep 4, 2018
by
anonymous

Describe the need of level measurements.
Last Answer : In almost all industries, vast quantities of liquid such as water ,solvents, chemicals etc. are used in number of processes. It is widely employed to monitor as well as measure ... and therefore its measurement becomes important in a variety of processes encountered in modern manufacturing plants.
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36 views
1 answer
asked
Jun 27, 2020
by
anonymous
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State the need of automation.
Last Answer : Need of Automation in Process : * To fulfill the demand of product at right time. * To reduce the human errors and involvement of human being in the process. * For better productivity. * For better ... of process. * For better quality. * For reducing man power. * For reducing cost of product.
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72 views
1 answer
asked
May 6, 2020
by
anonymous

Explain the need of maintenance of electrical equipment.
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66 views
0 answers
asked
Apr 27, 2020
by
anonymous

Explain the need and steps to conduct the reduced voltage running up test on the three phase induction motor.
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219 views
0 answers
asked
Apr 16, 2020
by
anonymous

Explain the need of energy conservation in present scenario.
Last Answer : Need of energy conservation in present scenario: 1. Fossil fuels like coal, oil which have taken no. of years to form and now they are on the verge of depleting soon. 2. In last ... protection and integrated economic and social development. 9. Energy saved is as good as energy generated.
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201 views
1 answer
asked
Sep 23, 2018
by
anonymous

Why do we need to correct power factor?
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62 views
0 answers
asked
Mar 10, 2018
by
anonymous

24 Transformer cores are laminated in order to A. simplify its construction B. minimise eddy current loss C. reduce cost D. reduce hysteresis loss
Last Answer : B. Minimise eddy current loss
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144 views
1 answer

What type of processor does the alienware m15x have?
Last Answer : http://www.laptopmag.com/review/laptops/alienware-m15x.aspx?mode=specs
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0 views
1 answer
asked
Feb 27
by
anonymous

The area of the yoke in a transformer is taken 15 to 20% larger than that of the core. Why?
Last Answer : By keeping yoke area 15-20% higher ,the flux density in the yoke is reduced, resulting into reduction in iron losses for yoke. The reduced core area results working flux density and needed to increase the number of turns.
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3 views
1 answer

What is the purpose of laminating the core in a transformer?
Last Answer : In order to minimize eddy current loss.
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2 views
1 answer

Where is core type and shell type construction suitable for a transformer?
Last Answer : Core type transformers are popular in High voltage applications like Distribution transformers, Power transformers, and obviously auto transformers. Where as, Shell type transformers are ... voltage applications like transformers used in electronic circuits and power electronic converters etc
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4 views
1 answer

What are the advantages of shell type transformer over core type transformers?
Last Answer : In shell type transformers the coils are well supported on the all sides and so they can withstand higher mechanical stresses developed during short circuit conditions. Also the leakage reactance will be less in shell type transformers.
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7 views
1 answer

72 Harmonics in transformer result in A. Increased core losses B. Increased I2R losses C. Magnetic interference with communication circuits D. All of the above
Last Answer : D. All of the above
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12 views
1 answer

[53] The iron loss of the transformer is negligible during short circuit test because A. The entire input is just sufficient to meet Cu losses only B. Flux produced is a small fraction of the normal flux C. Iron core becomes fully saturated D. Supply frequency is held constant
Last Answer : B. Flux produced is a small fraction of the normal flux
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54 views
1 answer
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49 The open circuit test is carried out in a transformer to find the A. Cu loss B. Core loss C. Total loss D. Insulation resistance
Last Answer : B. Core loss
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10 views
1 answer

46 The core used in high frequency transformer is usually A. Copper core B. Cost iron core C. Air core D.Mid steel core
Last Answer : C. Air core
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1 answer
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45 The function of conservator in a transformer is A. To protect against internal fault B. To reduce copper as well as core losses C. To cool the transformer oil D. To take care of the expansion and contraction of transformer oil due to variation of temperature of surroundings
Last Answer : D. To take care of the expansion and contraction of transformer oil due to variation of temperature of surroundings
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10 views
1 answer

43 The purpose of providing an iron core in a transformer is to A.Provide support to windings B. Reduce hysteresis loss C. decrease the reluctance of the magnetic path D. reduce eddy current losses
Last Answer : C. Decrease the reluctance of the magnetic path
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74 views
1 answer

27] In a transformer, the leakage flux of each winding is proportional to the current in that winding because A. Ohm's law applies to magnetic circuits B. Leakage paths do no saturate C. the two windings are electrically isolated D. mutual flux is confined to the core
Last Answer : B. Leakage path do not saturate
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166 views
1 answer

20] the main purpose of using core in a transformer is to A. Decrease iron losses B. prevent eddy current loss C. eliminate magnetic hysteresis D. decrease reluctance of the common magnetic circuit
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17 views
0 answers
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19 Transformer cores are built up from laminations rather than from solid metal so that A. Oil penetrates the core more easily B. Eddy current loss is reduced C. Less lamination is required for the windings D. Turn ratio is higher than voltage ratio
Last Answer : B. Eddy current loss is reduced
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72 views
1 answer
