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Name 10 different types of magnetic materials?
Co, Fe, FeOFe2O3, NiOFe2O3, CuOFe2O3, MgOFe2O3, MnBi, Ni, MnSb, MnOFe2O3
What material isolate magnetic field?
Materials such as mu-metal or permalloy are commonly used to isolate magnetic fields due to their high magnetic permeability, which allows them to redirect and absorb magnetic flux. These materials can be used to create shielding around sensitive equipment to block out external magnetic fields.
Types of ferromagnetic materials?
Some common types of ferromagnetic materials include iron, nickel, cobalt, and their alloys. These materials have strong magnetic properties due to the alignment of their atomic magnetic dipoles. Ferromagnetic materials are widely used in electromagnets, transformers, and various electronic devices.
What are some nine letter words with 2nd letter E and 4th letter M and 6th letter L and 9th letter Y?
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 2 words with the pattern -E-M-L--Y. That is, nine letter words with 2nd letter E and 4th letter M and 6th letter L and 9th letter Y. In alphabetical order, they are: gemmology permalloy
What are some nine letter words with 2nd letter E and 5th letter A and 6th letter L and 7th letter L?
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 7 words with the pattern -E--ALL--. That is, nine letter words with 2nd letter E and 5th letter A and 6th letter L and 7th letter L. In alphabetical order, they are: netballer permalloy redialled rentaller reswallow teocallis verballed
List of magnetic material?
Some common magnetic materials include iron, nickel, cobalt, and alloys like alnico and permalloy. These materials possess magnetic properties due to the alignment of their atomic dipoles, which allows them to create magnetic fields and attract or repel other magnets.
What materials shield magnetism and are electrically non-conductive?
basically magnetic fields can only be blocked or contained by conductive material such as the iron, electronic devices are shielded by metallic boxes to avoid interference. so, i don't think there's a known non conductive material that can block the magnetic field.
How do you make temporary magnets?
You can create temporary magnets by using a material that can be easily magnetized, such as iron or steel, and exposing it to a strong magnetic field. Once the magnetic field is removed, the material will lose its magnetism. Heating the material above its Curie temperature can also demagnetize it, making it temporary.
What are some nine letter words with 2nd letter E and 5th letter A and 6th letter L?
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 95 words with the pattern -E--AL---. That is, nine letter words with 2nd letter E and 5th letter A and 6th letter L. In alphabetical order, they are: aerialist aeriality bechalked beefaloes bengaline cembalist cephalate cephalics cephalins cephalous cerealist dentality dentalium descaling feudalise feudalism feudalist feudality feudalize genealogy genialise geniality genialize gerfalcon gestalten hemialgia herbalism herbalist jerfalcon kephalics kephalins lethality mentalese mentalism mentalist mentality mersalyls mescaline mescalins mescalism messaline metralgia mezcaline mezzaluna nephalism nephalist netballer neuralgia neuralgic pennalism pentalogy pentalpha peptalked percaline permalloy reanalyse reanalyze recoaling redealing redialing redialled rentaller repealers repealing requalify rescaling resealing ressaldar reswallow revealers revealing serialise serialism serialist seriality serialize sexualise sexualism sexualist sexuality sexualize sexvalent teocallis tervalent tetralogy veniality verbalise verbalism verbalist verbality verbalize verballed vernalise vernality vernalize
What is flux valve and its operation?
Fluxvalve Theory 10. The fluxvalve , consists of a sensitive pendulous element which is free to swing within limits (usually ± 25°) but fixed to the aircraft in azimuth. The element is suspended by a Hooke's Joint with the whole assembly being hermetically sealed in a case partially filled with oil to dampen oscillations. A deviation compensator is usually mounted on top of the unit. 73 Radio Magnetic Compass 11. The pendulous detector element resembles a three spoke wheel with the spokes 120° apart and slotted through the rim. The rim forms a collector horn for each spoke. The horns and spokes are made up of a series of metal laminations having a high magnetic permeability. Each spoke has a vertical cross-section similar to that shown in Fig 12-2. The spoke consists of two superimposed legs which are separated by plastic material and opened out to enclose the central hub cone. This cone has an exciter coil wound round it on a vertical axis, and each spoke has a pick-off coil wound round both legs on a horizontal axis. The exciter coil is fed with 400 Hz single phase AC. The output of the secondary or pick-off coil is an 800 Hz single phase AC current, the amplitude and phase representing the relationship of magnetic North to the aircraft longitudinal axis (magnetic heading). Fig 12-2: Vertical Cross-section of Spoke 12. In order to appreciate the operation of the fluxvalve it is necessary to consider an individual spoke. The function of a spoke will be developed in a series of diagrams (Figs 12-3 to 12-10). 13. If a single coil is placed in a magnetic field, the magnetic flux passing through the coil is maximum when the axis of the coil is in line with the direction of the field, zero when the coil lies at right angles to the field, and maximum but of opposite sense relative to the coil when turned 180° from its original position. For a coil placed at an angle θ to a field of strength H (Fig 12-3) the field can be resolved into two components, one along the coil equal to H cos θ and the other at right angles to the coil equal to H sin θ. The H cos θ component is parallel to the coil and is the effective flux producing element. Therefore, the total flux passing through the coil is proportional to the cosine of the angle between the direction of the coil axis and the direction of the field. The coil output curve is shown at Fig 12-4. If the coil is in the horizontal plane with its axis parallel with the aircraft longitudinal axis, its output is affected by the horizontal component of the Earth's magnetic field and the flux passing through the coil is proportional to the magnetic heading of the aircraft. Fig 12-3: Magnetic Flux Components Fig 12-4: Variation of Flux with Theta 14. Unfortunately, the simple concept just described cannot be used without modification as a heading reference system for two important reasons. Firstly, the voltage induced into a coil depends FIS Book 4: Instruments 74 on the rate of change of flux. Therefore, once established on a heading, there would be no change of flux and, consequently, no induced voltage. Secondly, the output of the simple detection device would be subject to heading ambiguity, i.e. there are always two headings which cause the same induced output voltage. Therefore, the problem that must be solved is how to produce an output waveform which is proportional in some way (frequency, phase or amplitude) to the components of the Earth's field and linked with the coil. This is achieved in the fluxvalve by introducing an alternating magnetic field in addition to the static field caused by the horizontal component of the Earth's magnetic field. 15. Fig 12-5 shows the relationship between flux density (B) and magnetizing force (H) known as the hysteresis loop for the permalloy commonly used in the legs of the flux valve spokes. Permalloy has a very high magnetic permeability (μ = B/H) and a corresponding low hysteresis loss. In the following discussion the hysteresis loop is represented by a single line curve. Fig 12-5: Hysteresis Curve for Permalloy Fig 12-6: Simple Fluxvalve Fig 12-7: The Effect of Excitation Current in the Top Leg Only 16. One spoke of the three-spoke fluxvalve is shown diagrammatically in Fig 12-6. It consists of a pair of soft iron (usually permalloy) cones each wound with a primary coil. The winding on one core is the reverse of that on the other. The AC supply is just sufficient, at peak power, to saturate magnetically each of the parallel soft iron cores. A secondary coil, wound round the two primaries, is linked with the circuit, and any change of flux through it induces a voltage and current flows. 17. Fig 12-7 shows the 400 Hz alternating flux induced in the top leg by the excitation current considering only the top leg of the spoke and the effect of the excitation. 75 Radio Magnetic Compass 18. Now considering the bottom leg only; the flux induced in this leg by the excitation current will at any instant be in the opposite direction to that induced in the top leg, i.e. the flux in the bottom leg is 180° out of phase with the flux in the top leg as shown in Fig 12-8. 19. Since the top and bottom legs are identical, the amplitudes of the flux of the two legs are equal but 180° out of phase with each other relative to the pick-off coil, which is wound round both legs. Therefore, the resultant flux cutting the pick-off coil, which is the algebraic sum of the flux in the top and bottom legs is zero as shown in Fig 12-9. Fig 12-9: The Effect of the Excitation Current in Both Legs Fig 12-8: The Effect of the Excitation Current in the Bottom Leg Only 20. If the horizontal component of the Earth's magnetic field (H) is now added in line with the spoke, it will induce a steady flux in both legs of the spoke which will be added to the flux due to the excitation current. The effect, as shown in Fig 12-10, will be to bias the datum for the magnetizing force, due to the excitation current, on the B-H curve by an amount equal to H. The strength of the excitation current is so arranged that the effect of the introduction of the Earth's magnetic field component is to bring the flux density curves in Fig 12-10 onto the saturation part of the hysteresis curve. The resultant flux cutting the pick-off coil, which is the algebraic sum of the fluxes in the top and bottom legs, will no longer be Fig 12-10: The Combine Effects of the Excitation Current and the Component of the Earth's Field zero but will have a resultant proportional in amplitude to heading. The emf induced in the pick-off coil FIS Book 4: Instruments 76 is proportional to the rate of change of flux cutting the coil and therefore will have a waveform approximating to a sine wave at 800 Hz, i.e. twice the frequency of the excitation current as shown in Fig 12-10. It has been found by experiment that the amplitude of the emf is proportional to H. Therefore, the emf in the pick-off coil is a measure of H, i.e. the horizontal component of the Earth's magnetic field in line with the spoke. This should be apparent from Fig 12-10 in that, if a greater H is detected, the excitation current is biased further from the mid-point of the hysteresis curve, and the imbalance between the upper and lower leg fluxes will increase. Therefore, a greater resultant flux exists which will induce an emf of greater amplitude in the pick-off coil. A plot of the amplitude of the pick-off coil output voltage would show that it varies as the cosine of the magnetic heading. 21. Limitations of the Simple Single Spoke Detector. It should be apparent that there are two magnetic headings corresponding to zero flux (90° and 270°) and two headings corresponding to a maximum flux. The two maximum values give the same reading on an AC voltmeter since the instrument cannot take into account the direction of the voltage. For any other value of flux (other than zero), there will be four headings corresponding to a single voltmeter reading. This ambiguity is overcome by using a fluxvalve having three spokes (each spoke similar to the single spoked device previously discussed) with 120° separation as shown in Fig 12-11. Regardless of the heading, at least two of the spokes will have a voltage induced and their vector sum points to magnetic North (Fig 12-12). The simple one-spoke detector suffers from another limitation in that the value of H changes with magnetic latitude. This produces a change in the static flux linking the spoke, even though the heading may remain unchanged. This limitation is Fig 12-11: Detector Unit and Transmission System - schematic Fig 12-12: Operation of the Three-spoke Fluxvalve Fig 12-13: Eliminating Latitude Ambiguity 77 Radio Magnetic Compass overcome in the three-spoke fluxvalve because the flux associated with each spoke will change in proportion to the change in H. The resultant field across the receiver stator is still aligned with H (Fig 12-13). 22. In the three-spoke fluxvalve a single primary coil excites all six cores. If a single arm of the fluxvalve is considered, it will be apparent that the top and the bottom of the exciter coil have opposite polarity. The flux induced in the upper core of the spoke is equal and opposite to that induced in the lower core and this is exactly the effect produced by the primary windings in the simple fluxvalve. The three arms of the fluxvalve are wound with secondary or pick-off coils which are star connected. The exciter coil is fed with 400 Hz single-phase current so that each of the three pick-off coils has an emf at 800 Hz induced in it whose amplitude is proportional to the magnetic heading of the aircraft. Each core of the fluxvalve is fitted with a flux collector horn to concentrate the Earth's lines of force through the core. This increases the static flux and therefore the induced voltage.
Why the semiconductor is used in electronic devices?
Electronic devices works with electric current (AC / DC), some conductors are used to control current by amplifying, change in voltage etc.All eletronic devices have its own power supply systemthat regulates electric current. These power system uses transfermer with diode and capacitors in old days but now transiter is used along with other as in smps. Main function of typical power suply system is to give electrical devices constant voltage/ current and save from sudden change in voltage. Sometime different part of electronic device requries different voltage electric current, which we have with power supply.Other systems of electronic devices are just controling/modifying current, frequency of electrical current, amplification etc. all this is done easily by semiconductor like transitor, diode etc.
