What is the difference between eddy current and hysteresis loss?
Last Answer : Loss occurred by magnetising and demagnetising process is called histerisis loss and the current flowed due to the magnetic field produced by the electric field applied is called eddy current losses
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Mar 15, 2018
by
anonymous

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.
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409 views
1 answer
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Mar 25, 2018
by
anonymous

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
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Apr 30, 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
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Mar 25, 2018
by
anonymous

The skin effect in conductors is due to non uniform distribution of current in it and major portion of current is near the _______ of conductor. (1) Surface (2) Center (3) Complete cross section area (4) Axis
Last Answer : The skin effect in conductors is due to non uniform distribution of current in it and major portion of current is near the Surface of conductor.
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271 views
1 answer
asked
Apr 30, 2018
by
anonymous

If the area of hysteresis loop of a material is large, the hysteresis loss in this material will be?
Last Answer : If the area of hysteresis loop of a material is large, the hysteresis loss in this material will be large.
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623 views
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Mar 25, 2018
by
anonymous

State the factors affecting hysteresis loss.
Last Answer : i) Flux density ii) Frequency iii) Volume of the magnetic material iv) Nature of magnetic material
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1 answer
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Sep 4, 2018
by
anonymous
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What is magnetic hysteresis? What is the cause of hysteresis?
Last Answer : Magnetic hysteresis: When a magnetic material is subjected to cycle of magnetization, it is found that flux density (B) in the material lags behind applied magnetizing force (H). This ... the movement of orientation, due to which the flux density lags behind the magnetic field intensity.
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Sep 4, 2018
by
anonymous

Last Answer : As hysteresis motors are free from mechanical and magnetic vibrations therefore these are considered as suitable for sound equipment.
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115 views
1 answer
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Mar 20, 2018
by
anonymous

Give two applications of each : 1) Eddy current sensor 2) Optical sensor.
Last Answer : Eddy current sensor : 1. Detection of non-magnetic but conductive materials. 2. Displacement sensing 3. Position sensing Optical sensor : 1. Position Detection 2. Velocity Detection 3. Acceleration Detection 4. Direction Detection
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93 views
1 answer
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Jul 21, 2019
by
anonymous

Which of the following can reduce the Eddy current losses? A) By making the core of a stack of plates electrically insulated from each other B) By making the core of solid block C) By increasing the applied voltage D) None of these
Last Answer : Which of the following can reduce the Eddy current losses? A) By making the core of a stack of plates electrically insulated from each other B) By making the core of solid block C) By increasing the applied voltage D) None of these
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1 answer
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Apr 29, 2018
by
anonymous

Eddy current damping cannot be used for moving iron instrument because
Last Answer : Eddy current damping cannot be used for moving iron instrument because the presence of a permanent magnet required for such purpose would affect the deflection and hence the reading of the instrument
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2.3k views
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Apr 26, 2018
by
anonymous

Last Answer : The disc of an instrument using eddy current damping should be of conducting and non-magnetic material.
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288 views
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Mar 21, 2018
by
anonymous

How eddy current can be minimized?
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Mar 15, 2018
by
anonymous

How eddy current is produced in a transformer?
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Mar 15, 2018
by
anonymous

what is eddy current ?
Last Answer : In magnetic circuits when we supply current to coil which wound on some core( of iron cast iron, ferrite ) material it produce magnetic field but there is small amount of flux which also ... heat and losses in magnetic circuits..for good working conditions we always try to minimize eddy current
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151 views
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asked
Aug 6, 2017
by
anonymous

Explain magnetic effect employed in measuring instrument.
Last Answer : Magnetic Effect: I) In PMMC meters: ➢ When a current is passed through a conductor, magnetic field is produced round the conductor. Due to this field when current ... field it experiences a mechanical force. Examples: Electrodynamometer type instruments, Induction type instrument.
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194 views
1 answer
asked
Sep 6, 2018
by
anonymous

Skin effect occurs when a conductor carries current at_____ frequencies.
Last Answer : Skin effect occurs when a conductor carries current at high frequencies.
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185 views
1 answer
asked
Mar 25, 2018
by
anonymous
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What is piezoelectric effect? Name two piezoelectric material.
Last Answer : piezoelectric effect: Piezoelectric effect can be stated as follows: when a pressure or force or vibration is applied to crystalline material like quartz crystal or crystalline substances, then ... crystal: Quartz crystal ,Rochelle salt 2) Synthetic crystals : Barium Titanate, Lithium sulphate
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1 answer
asked
Sep 8, 2018
by
anonymous

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
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May 7, 2020
by
anonymous

The magnetic susceptibility of paramagnetic material is: A) Less than zero B) Less than one but positive C) Greater than one D) Equal to zero
Last Answer : The magnetic susceptibility of paramagnetic material is: Less than one but positive
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229 views
1 answer
asked
Jun 18, 2018
by
anonymous

The property of a material which opposes the creation of magnetic flux in it is known as?
Last Answer : The property of a material which opposes the creation of magnetic flux in it is known as reluctance.
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2.0k views
1 answer
asked
Mar 25, 2018
by
anonymous

A material for good magnetic memory should have?
Last Answer : A material for good magnetic memory should have high retentivity.
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167 views
1 answer
asked
Mar 25, 2018
by
anonymous

Last Answer : Yes, Induction heating is used for both magnetic and non-magnetic materials.
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102 views
1 answer
asked
Mar 6, 2018
by
anonymous

explain skin effect in copper interconnects. what are the various ways of reducing this effect?
Last Answer : Skin effect generally observed in ac conductor in transmission network, in skin the current flowing through outer layer of conductor is more than iner area of conductor thus we can say the ... for reducing this effect we can use boundel conductor or used hollow conductor for power transmission
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100 views
1 answer
asked
Dec 13, 2017
by
anonymous
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Define armature reaction in an alternator. Explain the effect of armature reaction at various P.F. of loads of alternator.
Last Answer : Armature Reaction: The effect of armature flux on main flux is called as armature reaction. Armature Reaction at Various Power Factors: When armature is loaded, the armature flux modifies ... lagging p.f. For capacitive loads the effect of flux is partly distorting and partly strengthening.
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421 views
1 answer
asked
May 7, 2020
by
anonymous

Classify magnetic materials and explain in brief.
Last Answer : .embed-container { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; } .embed-container iframe, .embed-container object, .embed-container embed { ... the absence of external magnetic field. Following are the ferromagnetic materials: Iron, Cobalt, Nickel.
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288 views
1 answer
asked
Sep 4, 2018
by
anonymous

State the disadvantages of skin effect.
Last Answer : Disadvantages of skin effect:- 1. Full cross section of conductor is not utilized, Therefore effective area of conductor reduces so its resistance increases. 2. Due to increase in resistance, copper ... increases (Since Voltage drop = IR ) 5. So voltage regulation becomes poor (increases)
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250 views
1 answer
asked
May 22, 2020
by
anonymous

State the meaning of skin effect and how can it be minimised.
Last Answer : Meaning of skin effect : When alternating current flows through conductor it has tendency to flow away from center of conductor. i.e. maximum current density is near skin of conductor and goes on ... whenever possible as Skin effect is absent (Since frequency 0) instead of A.C. supply.
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79 views
1 answer
asked
May 22, 2020
by
anonymous

Skin effect is absent in which of the following transmission systems? A) Extra High Voltage (EHV) AC B) High Voltage Direct Current (HVDC) C) Both A and B D) None of these
Last Answer : Skin effect is absent in which of the following transmission systems? A) Extra High Voltage (EHV) AC B) High Voltage Direct Current (HVDC) C) Both A and B D) None of these
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156 views
1 answer
asked
Apr 29, 2018
by
anonymous
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when the skin effect occurs ?
Last Answer : skin effect is occur at higher frequencies when skin depth is smaller
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105 views
1 answer
asked
Aug 18, 2017
by
anonymous

what is skin effect?
Last Answer : Skin effect is occurs in conductor due to high frequency...as the frequency increases the resistance of conductor increases...skin effect means the current flow through the skin of conductor....as the ... dc current their will be no skin effect...I hope you understand basic concept of skin effect
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247 views
2 answers
asked
Aug 6, 2017
by
anonymous

Explain the characteristics of inductor to be considered while designing it. What is the effect of over current and increase in temperature on inductor.
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69 views
0 answers
asked
Mar 10, 2018
by
anonymous
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Analyze the effect of supply voltage on performance of LED as regards current, Lumen output, efficacy and life.
Last Answer : 1) Effect on Current:- In LED current depends upon supply voltage, if voltage get changes then current also change but this change in current will be control by resistors which are connected in series. 2) ... 4) Effect on Life:- If supply voltage is not stable then life of LED get reduced.
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106 views
1 answer
asked
May 3, 2020
by
anonymous

With the help of N-channel JFET describe the effect of input voltage VGS on output current ID.
Last Answer : Working of N channel FET: * When a voltage is applied between the drain and source with a DC supply (VDD), the electrons flows from source to drain through narrow channel ... where the channel gets completely blocked and the drain current becomes zero is called pinch- off voltage.
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231 views
1 answer
asked
May 2, 2020
by
anonymous

Last Answer : The chemical effect of current is used in D.C. ammeter hour meter.
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85 views
1 answer
asked
Mar 21, 2018
by
anonymous

Explain the hysteresis loop of a magnetic material with neat diagram.
Last Answer : Hysteresis loop of magnetic material: The circuit arrangement for plotting the hysteresis loop is shown in figure given below. The electromagnetic part consists of a coil wound on the iron ring ... one magnetic reversal is called hysteresis loop. Meaning of hysteresis is to lag behind.
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662 views
1 answer
asked
Aug 8, 2018
by
anonymous

In a loss-free R-L-C circuit the transient current is?
Last Answer : In a loss-free R-L-C circuit the transient current is sinusoidal.
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403 views
1 answer
asked
Mar 25, 2018
by
anonymous

How can a magnetic field be used to generate an electric current?
Last Answer : Magnetic field can be used to generate electric current on a condition that it is on a rate of changing magnetic flux. (Faraday's law)
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106 views
1 answer
asked
Mar 10, 2018
by
anonymous

Explain why potential difference is necessary to produce current in a circuit.
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99 views
0 answers
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Jun 29, 2019
by
anonymous

List and state any four limitations of inter connected power station.
Last Answer : Limitations of inter connected power station:- 1) Initial cost of infrastructure of transmission line increases as length increases. 2) Interconnection required more automation which increases cost on ... capacity. But in absence of surplus power merits of interconnection cannot be obtain.
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47 views
1 answer
asked
Sep 8, 2018
by
anonymous

State any two limitations of wind energy.
Last Answer : Limitations of wind energy: 1) Wind turbine produces noise. 2) Its efficiency is less (20% to 30%) 3) There is limitation on site selection. 4) Transportation cost of wind tower and accessories is high ... No firm power. 7) Power generation is not in phase with the demand. 8) Generation is costly.
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73 views
1 answer
asked
Sep 7, 2018
by
anonymous

Eddy currents are induced in the pole shoes of a D.C. machine due to?
Last Answer : Eddy currents are induced in the pole shoes of a D.C. machine due to relative rotation between field and armature.
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1 answer
asked
Mar 20, 2018
by
anonymous

How eddy currents are generated?
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0 answers
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Mar 14, 2018
by
anonymous

Describe with neat sketch working of hysteresis motor.
Last Answer : Working: When stator is energized with single phase ac supply, rotating magnetic field is produced because of starting (auxiliary) and main windings, which remain in circuit permanently. The ... the principle of magnetic locking this motor either rotates at synchronous speed or not at all.
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203 views
1 answer
asked
May 7, 2020
by
anonymous

Hysteresis is commonly found in ______ A) ferromagnetic materials B) ferroelectric materials C) both A and B D) none of these
Last Answer : Hysteresis is commonly found in ______ A) ferromagnetic materials B) ferroelectric materials C) both A and B D) none of these
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125 views
1 answer
asked
Apr 29, 2018
by
anonymous

The term hysteresis is associated with (A) On-Off control (B) P-I control (C) Feed forward control (D) Ratio control
Last Answer : The term hysteresis is associated with On-Off control
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1 answer
asked
Apr 26, 2018
by
anonymous

Last Answer : The rotor of a hysteresis motor is made of chrome steel.
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1 answer
asked
Mar 20, 2018
by
anonymous
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Last Answer : In a hysteresis motor, the rotor must have retentivity.
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73 views
1 answer
asked
Mar 20, 2018
by
anonymous

Last Answer : A hysteresis motor works on the principle of hysteresis loss.
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121 views
1 answer
asked
Mar 20, 2018
by
anonymous
