Magnet sentence example

magnet
  • You're like a magnet lately.
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  • He moved the magnet and plucked the picture from the door.
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  • Sticking it to the refrigerator with a magnet, she headed for the barn.
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  • It is also possible that a magnet may have no poles at all.
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  • If, for example, a knitting needle is stroked with the south pole of a magnet, the strokes being directed from the middle of the needle towards the two extremities alternately, the needle will acquire a north pole at each end and a south pole in the middle.
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  • Outside the magnet the direction of the magnetic induction is generally the same as that of the magnetic force.
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  • A sheet of cardboard is placed above the magnet, and some iron filings are sifted thinly and evenly over the surface: if the cardboard is gently tapped, the filings will arrange themselves in a series of curves, as shown in fig.
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  • A much better form of electromagnetic ammeter can be constructed on a principle now extensively employed, which consists in pivoting in the strong field of a permanent magnet a small coil through which a part of the current to be measured is sent.
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  • Such a combination constitutes an electromagnet, a valuable device by means of which a magnet can be instantly made and unmade at will.
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  • For our complete range of handles, see our Magnet Collections brochure or visit your nearest Magnet showroom.
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  • However, I still had no idea whether the magnet treatment to my own arm was only symptomatic or could eventually promote complete healing.
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  • Faraday's discovery of the induced current produced by passing a magnet through a helix of wire forming part of a closed circuit was laid hold of in the telegraph of Gauss and Weber, and this application was at the request of Gauss taken up by Steinheil, who brought it to considerable perfection.
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  • When a current comes in from line it passes through the electromagnet in such a direction as to weaken the effect of the permanent magnet; hence the springs are able to release the armature, which rises smartly and in its turn releases the printing mechanism.
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  • His first idea seems to have been to employ the vibrations of the current in an electric circuit, produced by moving the armature of an electromagnet included in the circuit nearer to or farther from the poles of the magnet.
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  • The entire board is magnetized so displaying photos is as simple as placing a magnet in each photo corner.
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  • Go the extra mile by stuffing a little something else in the envelope, such as a gift card to a favorite coffee shop, confetti, or a quotable magnet.
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  • With dozens of online retailers offering a wide range of personalized magnet styles, it is easy to find a magnet to coordinate with your wedding.
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  • Most customized magnet dealers have a variety of options to suit a couple's preferences.
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  • Pictures: Many magnet companies allow the couple to include a personal picture on the magnet, which is a great way to share engagement photos or a fun snapshot so guests can see the couple together.
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  • The magnet's orientation may also be able to change and couples could select either horizontal or vertical magnets.
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  • Text: Naturally the couple will want their names and the upcoming wedding date on the magnet, but some retailers also allow short phrases or sentimental sayings on the magnets to add more flair.
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  • Many have a snap, magnet, or zipper to fasten it closed.
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  • It is often sufficient to find the ratio of the moment of one magnet to that of another.
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  • Let 0 be the angle which the standard magnet M makes with the meridian, then M'/R = sin 0, and M/R = cos 0, whence M' = M tan 0.
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  • A compass having a very short needle is placed on the line which bisects the axis of the magnet at right angles, and is moved until a neutral point is found where the force due to the earth's field H is balanced by that due to the magnet.
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  • The distance between the poles may with sufficient accuracy for a rough determination be assumed to be equal to five-sixths of the length of the magnet.
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  • The sample, arranged as a bundle of rectangular strips, is caused to rotate about a central horizontal axis between the poles of an upright C-shaped magnet, which is supported near 'its middle upon knife-edges in such a manner that it can oscillate about an axis in a line with that about which the specimen rotates; the lower side of the magnet is weighted, to give it some stability.
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  • When the specimen rotates, the magnet is deflected from its upright position by an amount which depends upon the work done in a single complete rotation, and therefore upon the hysteresis.
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  • Ewing has described an arrangement in which the test bar has a soft-iron pole piece clamped to each of its ends; the pole pieces are joined by a long well-fitting block of iron, which is placed upon them (like the " keeper " of a magnet), and the induction is measured by the force required to detach the block.
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  • Tractive Force of a Magnet.-Closely connected with the results just discussed is the question what is the greatest tractive force that can be exerted by a magnet.
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  • It is suggested that a permanent magnet might conveniently be " aged " (or brought into a constant condition) by dipping it several times into liquid air.
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  • Weber's theory, the molecules of a ferromagnetic metal are small permanent magnets, the axes of which under ordinary conditions are turned indifferently in every direction, so that no magnetic polarity is exhibited by the metal as a whole; a magnetic force acting upon the metal tends to turn the axes of the little magnets in one direction, and thus the entire piece acquires the properties of a magnet.
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  • It can be shown that if a current i circulates in a small plane circuit of area S, the magnetic action of the circuit for distant points is equivalent to that of a short magnet whose axis is perpendicular to the plane of the circuit and whose moment is iS, the direction of the magnetization being related to that of the circulating current as the thrust of a right-handed screw to its rotation.
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  • The creation of an external magnetic field H will, in accordance with Lenz's law, induce in the molecule an electric current so directed that the magnetization of the equivalent magnet is opposed to the direction of the field.
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  • If S is the area of the orbit described in time T by an electron of charge e, the moment of the equivalent magnet is M = eST; and the change in the value of M due to an external field H is shown to be OM = - He'S/47rm, m being the mass of the electron.
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  • If the structure of the molecule is so perfectly symmetrical that, in the absence of any external field, the resultant magnetic moment of the circulating electrons is zero, then the application of a field, by accelerating the right-handed (negative) revolutions, and retarding those which are left-handed, will induce in the substance a resultant magnetization opposite in direction to the field itself; a body composed of such symmetrical molecules is therefore diamagnetic. If however the structure of the molecule is such that the electrons revolving around its atoms do not exactly cancel one another's effects, the molecule constitutes a little magnet, which under the influence of an external field will tend to set itself with its axis parallel to the field.
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  • The property of orientation, in virtue of which a freely suspended magnet points approximately to the geographical north and south, is not referred to by any European writer before the 12th century, though it is said to have been known to the Chinese at a much earlier period.
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  • The greatest of Gilbert's discoveries was that the globe of the earth was magnetic and a magnet; the evidence by which he supported this view was derived chiefly from ingenious experiments made with a spherical lodestone or lerrella, as he termed it, and from his original observation that an iron bar could be magnetized by the earth's force.
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  • C. Oersted 6 that a magnet placed near a wire carrying an electric current tended to set itself at right angles to the wire, a phenomenon which indicated that the current was surrounded by a magnetic field.
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  • Ampere's experimental and theoretical investigation of the mutual action of electric currents, and of the equivalence of a closed circuit to a polar magnet, the latter suggesting his celebrated hypothesis that molecular currents were the cause of magnetism.
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  • C. Oersted (1777-1851) had shown that a magnetic needle is deflected by an electric current, he attempted, in the laboratory of the Royal Institution in the presence of Humphry Davy, to convert that deflection into a continuous rotation, and also to obtain the reciprocal effect of a current rotating round a magnet.
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  • It was probably in Paris, the chief intellectual centre of his time, that Neckam heard how a ship, among its other stores, must have a needle placed above a magnet (the De utensilibus assumes a needle mounted on a pivot), which needle would revolve until its point looked north, and thus guide sailors in murky weather or on starless nights.
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  • His prize subjects were, the capstan, the propagation of light, and the magnet.
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  • In its improved form this meter consists of a single horseshoe permanent magnet formed of tungsten-steel having a strong and constant field.
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  • The driving force is balanced against a retarding force produced by the rotation of a copper disk fixed on the armature shaft, which rotates between the poles of a permanent magnet.
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  • By the use of a permanent magnet instead of a shunt coil as the bob of one pendulum, the meter can be made up as an ampere-hour meter.
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  • The geometrical axis of the magnet is sometimes defined by means of a mirror rigidly attached to the magnet and having the normal to the mirror as nearly as may be parallel to the magnetic axis.
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  • For this reason the end of the magnet is sometimes polished and acts as the mirror, in which case no displacement of the reflecting surface with reference to the magnet is possible.
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  • A different arrangement, used in the instrument described below, consists in having the magnet hollow, with a small scale engraved on glass firmly attached at one end, while to the other end is attached a lens, so chosen that the scale is at its principal focus.
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  • The position of the magnet is observed by means of a small telescope, and since the scale is at the principal focus of the lens, the scale will be in focus when the telescope is adjusted to observe a distant object.
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  • Thus no alteration in the focus of the telescope is necessary whether we are observing the magnet, a distant fixed mark, or the sun.
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  • The magnet is protected from draughts by the box A, which is closed at the sides by two shutters when an observation is being taken.
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  • The telescope B serves to observe the scale attached to the magnet when determining the magnetic meridian, and to observe the sun or star when determining the geographical meridian.
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  • When making a determination of declination a brass plummet having the same weight as the magnet is first suspended in its place, and the torsion of the fibre is taken out.
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  • The magnet having been attached, the instrument is rotated about its vertical axis till the centre division of the scale appears to coincide with the vertical cross-wire of the telescope.
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  • The two verniers on the azimuth circle having been read, the magnet is then inverted, i.e.
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  • A second setting with the magnet inverted is generally made, and then another setting with the magnet in its original position.
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  • For this reason some observers use a thin strip of phosphor bronze to suspend the magnet, considering that the absence of a variable torsion more than compensates for the increased difficulty in handling the more fragile metallic suspension.
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  • The method of measuring the horizontal component which is almost exclusively used, both in fixed observatories and in the field, consists in observing the period of a freely suspended magnet, and then obtaining the angle through which an auxiliary suspended magnet is deflected by the magnet used in the first part of the experiment.
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  • In the case of the Kew pattern unifilar the same magnet that is used for the declination is usually employed for determining H, and for the purposes of the vibration experiment it is mounted as for the observation of the magnetic meridian.
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  • The auxiliary magnet has a plane mirror attached, the plane of which is at right angles to the axis of the magnet.
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  • The axis of the magnet is horizontal and at the same level as the mirror magnet, while when the central division of the scale B appears to coincide with the vertical cross-wire of the telescope the axes of the two magnets are at right angles.
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  • During the experiment the mirror magnet is protected from draughts by two wooden doors which slide in grooves.
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  • What is known as the method of sines is used, for since the axes of the two magnets are always at right angles when the mirror magnet is in its zero position, the ratio M/H is proportional to the sine of the angle between the magnetic axis of the mirror magnet and the magnetic - = meridian.
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  • When conducting a deflexion experiment the de flecting magnet K is placed with its centre at 30 cm.
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  • The magnet K is then reversed in the support, and a new setting taken.
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  • The difference between the two sets of readings gives twice the angle which the magnetic axis of the mirror magnet makes with the magnetic meridian.
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  • In order to eliminate any error due to the zero of the scale D not being exactly below the mirror magnet, the support L is then removed to the west side of the instrument, and the settings are repeated.
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  • Further, to allow of a correction being applied for the finite length of the magnets the whole series of settings is repeated with the centre of the deflecting magnet at 40 cm.
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  • Omitting correction terms depending on the temperature and on the inductive effect of the earth's magnetism on the moment of the deflecting magnet, if 0 is the angle which the axis of the deflected magnet makes with the meridian when the centre of the deflecting magnet is at a distance r, then zM sin B=I+P+y2 &c., in which P and Q are constants depending on the dimensions and magnetic states of the two magnets.
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  • Thus it is usual, if the magnets are of similar shape, to make the deflected magnet 0.467 of the length of the deflecting magnet, in which case Q is negligible, and thus by means of deflexion experiments at two distances the value of P can be obtained.
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  • If the temperature of the magnet were always exactly the same in both the vibration and FIG 2.
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  • The fact that the moment of inertia of the magnet varies witli the temperature must, however, be taken into account.
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  • In the deflexion experiment, in addition to the induction correction, and that for the effect of temperature on the magnetic moment, a correction has to be applied for the effect of temperature on the length of the bar which supports the deflexion magnet.
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  • In order to obtain the declination a pivoted magnet is used to obtain the magnetic meridian, the geographical meridian being obtained by observations on the sun or stars.
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  • The principle of the method consists in deflecting the compass needle by means of a horizontal magnet supported vertically over the compass card, the axis of the deflecting magnet being always perpendicular to the axis of the magnet attached to the card.
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  • The method is not strictly an absolute one, since it presupposes a knowledge of the magnetic moment of the deflecting magnet.
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  • In practice it is found that a magnet can be prepared which, when suitably protected from shock, &c., retains its magnetic moment sufficiently constant to enable observations of H to be made comparable in accuracy with that of the other elements obtained by the instruments ordinarily employed at sea.
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  • By 1891 he had designed and erected at the Royal Institution an apparatus which yielded liquid oxygen by the pint, and towards the end of that year he showed that both liquid oxygen and liquid ozone are strongly attracted by a magnet.
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  • The mariner's compass, with which this article is concerned, is an instrument by means of which the directive force of that great magnet, the Earth, upon a freely-suspended needle, is utilized for a purpose essential to navigation.
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  • The hull of an iron or steel ship is a magnet, and the distribution of its magnetism depends upon the direction of the ship's head when building, this result being produced by induction from the earth's magnetism, developed and impressed by the hammering of the plates and frames during the process of building.
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  • With the deflector any inequality in the directive force can be detected, and hence the power of equalizing the forces by the usual soft iron and magnet correctors.
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  • The Chinese name for the compass is ting-nan-ching, or needle pointing to the south; and a distinguishing mark is fixed on the magnet's southern pole, as in European compasses upon the northern one."
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  • The Italian name of calamita, which still persists, for the magnet, and which literally signifies a frog, is doubtless derived from this practice.
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  • The magnetical needle, and its suspension on a stick or straw in water, are clearly described in La Bible Guiot, a poem probably of the r3th century, by Guiot de Provins, wherein we are told that through the magnet (la manette or l'amaniere), an ugly brown stone to which iron turns of its own accord, mariners possess an art that cannot fail them.
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  • In Scandinavian records there is a reference to the nautical use of the magnet in the Hauksbok, the last edition of the LandndmabOk (Book of the Colonization of Iceland): - "Floki, son of Vilgerd, instituted a great sacrifice, and consecrated three ravens which should show him the way (to Iceland); for at that time no men sailing the high seas had lodestones up in northern lands."
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  • All that is certain is a knowledge of the nautical use of the magnet at the end of the r3th century.
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  • Prior to this clear description of a pivoted compass by Peregrinus in 1269, the Italian sailors had used the floating magnet, probably introduced into this region of the Mediterranean by traders belonging to the port of Amalfi, as commemorated in the line of the poet Panormita: "Prima dedit nautis usum magnetis Amalphis."
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  • In 1511 Baptista Pio in his Commentary repeats the opinion as to the invention of the use of the magnet at Amalfi as related by Flavius.
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  • Gyraldus, writing in 1540 (Libellus de re nautica), misunderstanding this reference, declared that this observation of the direction of the magnet to the poles had been handed down as discovered "by a certain Flavius."
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  • A specimen of one of these heavy glasses afterwards became historically important as the substance in which Faraday detected the rotation of the plane of polarization of light when the glass was placed in the magnetic field, and also as the substance which was first repelled by the poles of the magnet.
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  • This led him in the beginning of September to discover the method of producing the continuous rotation of the wire round the magnet, and of the magnet round the wire.
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  • He did not succeed in making the wire or the magnet revolve on its own axis.
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  • Ampere, Wollaston and others, the realization of the continuous rotation of the wire and the magnet round each other was a scientific puzzle requiring no mean ingenuity for its original solution.
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  • For on the one hand the electric current always forms a closed circuit, and on the other the two poles of the magnet have equal but opposite properties, and are inseparably connected, so that whatever tendency there is for one pole to circulate round the current in one direction is opposed by the equal tendency of the other pole to go round the other way, and thus the one pole can neither drag the other round and round the wire nor yet leave it behind.
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  • The thing cannot be done unless we adopt in some form Faraday's ingenious solution, by causing the current, in some part of its course, to divide into two channels, one on each side of the magnet, in such a way that during the revolution of the magnet the current is transferred from the channel in front of the magnet to the channel behind it, so that the middle of the magnet can pass across the current without stopping it, just as Cyrus caused his army to pass dryshod over the Gyndes by diverting the river into a channel cut for it in his rear.
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  • In December 1824 he had attempted to obtain an electric current by means of a magnet, and on three occasions he had made elaborate but unsuccessful attempts to produce a current in one wire by means of a current in another wire or by a magnet.
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  • He endeavoured, but in vain, to detect any change in the lines of the spectrum of a flame when the flame was acted on by a powerful magnet.
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  • On the 3rd of November a new horseshoe magnet came home, and Faraday immediately began to experiment on the action in the polarized ray through gases, but with no effect.
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  • A bar of heavy glass was suspended by silk between the poles of the new magnet.
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  • From Aristotle we learn (I) that Thales found in water the origin of things; (2) that he conceived the earth to float upon a sea of the elemental fluid; (3) that he supposed all things to be full of gods; (4) that in virtue of the attraction exercised by the magnet he attributed to it a soul.
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  • In Se p tember of that year he discovered that the force required for the rotation of a copper disk becomes greater when it is made to rotate with its rim between the poles of a magnet, the disk at the same time becoming heated by the eddy or "Foucault currents" induced in its metal.
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  • M-P; because, though both end in a universal conclusion, the limits of experience prevent induction from such inference as: Every experienced magnet attracts iron.
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  • Every magnet whatever is every experienced magnet..
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  • Every magnet whatever attracts iron.
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  • This view makes inference easy: induction is all over before it begins; for, according to Bradley, " every one of the instances is already a universal proposition; and it is not a particular fact or phenomenon at all," so that the moment you observe that this magnet attracts iron, you ipso facto know that every magnet does so, and all that remains for deduction is to identify a second magnet as the same with the first, and conclude that it attracts iron.
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  • Hence also induction is a real process, because, when we know that this individual magnet attracts iron, we are very far from knowing that all alike do so similarly; and the question of inductive logic, how we get from some similars to all similars, remains, as before, a difficulty, but not to be solved by the fallacy that inference is identification.
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  • The changes in declination are obtained by means of a magnet which is suspended by a long fibre and carries a mirror, immediately below which a fixed mirror is attached to the base of the instrument.
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  • Light passing through a vertical slit falls upon the mirrors, from which it is reflected, and two images of the slit are produced, one by the movable mirror attached to the magnet and the other by the fixed mirror.
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  • As the declination changes the spot of light reflected from the magnet mirror moves parallel to the axis of the recording drum, and hence the distance between the line traced by this spot and the base line gives, for any instant, on an arbitrary scale the difference between the declination and a constant angle, namely, the declination corresponding to the base line.
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  • The value in terms of arc of the scale of the record can be obtained by measuring the distance between the magnet mirror and the recording drum, and in most observations it is such that a millimetre on the record represents one minute of arc. The time scale ordinarily employed is 15 mm.
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  • The variation of the horizontal force is obtained by the motion of a magnet which is carried either by a bifilar suspension or by a fairly stiff metal wire or quartz fibre.
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  • The upper end of the suspension is turned till the axis of the magnet is at right angles to the magnetic meridian.
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  • In this position the magnet is in equilibrium under the action of the torsion of the suspension and the couple exerted by the horizontal component, H, of the earth's field, this couple depending on the product of H into the magnetic moment, M, of the magnet.
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  • Since the movements of the magnet are always small, the rotation of the magnet is proportional to the change in H, so long as M and the couple, 0, corresponding to unit twist of the suspension system remain constant.
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  • Since such a decrease in 0 would by itself cause the magnet to turn in the same direction as if H had increased, it is possible in a great measure to neutralize the effects of temperature on the reading of the instrument.
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  • In the Eschenhagen pattern instrument, in which a single quartz fibre is used for the suspension, two magnets are placed in the vicinity of the suspended magnet and are so arranged that their field partly neutralizes the earth's field; thus the torsion required to hold the magnet with its axis perpendicular to the earth's field is reduced, and the arrangement permits of the sensitiveness being altered by changing the position of the deflecting magnets.
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  • To record the variations of the vertical component use is made of a magnet mounted on knife edges so that it can turn freely about a horizontal axis at right angles to its 1 Report British Association, Bristol, 18 9 8, P. 741.
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  • The magnet is so weighted that its axis is approximately horizontal, and any change in the inclination of the axis is observed by means of an attached mirror, a second mirror fixed to the stand serving to give a base line for the records, which are obtained in the same way as in the case of the declination.
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  • The magnet is in equilibrium under the influence of the couple VM due to the vertical component V, and the couple due to the fact that the centre of gravity is slightly on one side of the knife-edge.
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  • Hence when, say, V decreases the couple VM decreases, and hence the north end of the balanced magnet rises, and vice versa.
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  • To reduce these effects the magnet is fitted with compensating bars, generally of zinc, so adjusted by trial that as far as possible they neutralize the effect of changes of temperature.
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  • The temperature compensation is obtained by attaching a small weight to the magnet, and then bringing it back to the horizontal position by twisting the fibre.
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  • The scale values of the records given by the horizontal and vertical force magnetographs are determined by deflecting the respective needles, either by means of a magnet placed at a known distance or by passing an electric current through circular coils of large diameter surrounding the instruments.
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  • To overcome this difficulty Eschenhagen in his earlier type of instruments attached to each magnet two mirrors, their planes being inclined at a small angle so that when the spot reflected from one mirror goes off the paper, that corresponding to the other comes on.
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  • By this arrangement the angular rotation of the reflected beam is less than that of the magnet, and hence the spot of light reflected from this mirror yields a trace on a much smaller scale than that given by the ordinary mirror and serves to give a complete record of even the most energetic disturbance.
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  • Oersted's important discovery was the fact that when a wire joining the end plates of a voltaic pile is held near a pivoted magnet or compass needle, the latter is deflected and places itself more or less transversely to the wire, the direction depending upon whether the wire is above or below the needle, and on the manner in which the copper or zinc ends of the pile are connected to it.
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  • In 1821 Michael Faraday (1791-1867), who was destined later on to do so much for the science of electricity, discovered electromagnetic rotation, having succeeded in causing a wire conveying a voltaic current to rotate continuously round the pole of a permanent magnet.
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  • The study of the relation between the magnet and the circuit conveying an electric current then led Arago to the discovery of the " magnetism of rotation."
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  • He found that a vibrating magnetic compass needle came to rest sooner when placed over a plate of copper than otherwise, and also that a plate of copper rotating under a suspended magnet tended to drag the magnet in the same direction.
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  • Faraday and others then discovered, as already mentioned, means to make the conductor conveying the current rotate round a magnetic pole, and Ampere showed that a magnet could be made to rotate on its own axis when a current was passed through it.
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  • The difficulty in this case consisted in discovering means by which the current could be passed through one half of the magnet without passing it through the other half.
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  • This, however, was overcome by sending the current out at the centre of the magnet by means of a short length of wire dipping into an annular groove containing mercury.
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  • Barlow, Sturgeon and others then showed that a copper disk could be made to rotate between the poles of a horseshoe magnet when a current was passed through the disk from the centre to the circumference, the disk being rendered at the same time freely movable by making a contact with the circumference by means of a mercury trough.
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  • Amongst the memorable achievements of the ten days which Faraday devoted to this investigation was the discovery that a current could be induced in a conducting wire simply by moving it in the neighbourhood of a magnet.
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  • One form which this experiment took was that of rotating a copper disk between the poles of a powerful electric magnet.
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  • To him a magnet was not simply a bar of steel; it was the core and origin of a system of lines of magnetic force attached to it and moving with it.
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  • Faraday's copper disk rotated between the poles of a magnet, and producing thereby an electric current, became the parent of 1 See also his Submarine Telegraphs (London, 1898).
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  • It consisted of a fixed horseshoe armature wound over with insulated copper wire in front of which revolved about a vertical axis a horseshoe magnet.
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  • Siemens effected a great improvement by inventing a shuttle armature and improving the shape of the field magnet.
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  • This work, which embodied the results of many years' research, was distinguished by its strict adherence to the scientific method of investigation by experiment, and by the originality of its matter, containing, as it does, an account of the author's experiments on magnets and magnetical bodies and on electrical attractions, and also his great conception that the earth is nothing but a large magnet, and that it is this which explains, not only the direction of the magnetic needle north and south, but also the variation and dipping or inclination of the needle.
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  • Henry appears to have been the first to adopt insulated or silkcovered wire for the magnetic coil; and also the first to employ what may be called the "spool" winding for the limbs of the magnet.
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  • He was also the first to demonstrate experimentally the difference of action between what he called a "quantity" magnet excited by a "quantity" battery of a single pair, and an "intensity" magnet with long fine wire coil excited by an "intensity" battery of many elements, having their resistances suitably proportioned.
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  • Early in 1831 he arranged a small office-bell to be tapped by the polarized armature of an "intensity" magnet, whose coil was in continuation of a mile of insulated copper wire, suspended about one of the rooms of his academy.
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  • This was the first instance of magnetizing iron at a distance, or of a suitable combination of magnet and battery being so arranged as to be capable of such action.
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  • In 1835 he combined the short circuit of his monster magnet (of 1834) with the small "intensity" magnet of an experimental telegraph wire, thereby establishing the fact that very powerful mechanical effects could be produced at a great distance by the agency of a very feeble magnet used as a circuit maker and breaker, or as a "trigger" - the precursor of later forms of relay and receiving magnets.
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  • It is attracted by a magnet and may be magnetized, but the magnetization is quickly lost.
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  • This important ore of iron is most celebrated for its magnetic properties (see Magnetism and Compass), but the mineral is not always magnetic, although invariably attracted by a magnet.
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  • It dissolves in acids to form a mixture of a ferrous and ferric salt,' and if an alkali is added to the solution a black precipitate is obtained which dries to a dark brown mass of the composition Fe(OH)2Fe203; this substance is attracted by a magnet, and thus may be separated from the admixed ferric oxide.
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  • It has a somewhat brassy colour, and occurs massive or as hexagonal plates; it is attracted by a magnet and is sometimes itself magnetic. The mineral is abundant in Canada, where the presence of about 5% of nickel makes it a valuable ore of this metal.
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  • You want to find a needle in a haystack, get a magnet.
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  • Striding back to the kitchen, he deliberately removed the caduceus magnet and centered the picture on the refrigerator door – eye level.
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  • The length of exposure to a magnet for healing certain ailments was also determined.
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  • In a discussion with Mitchy recently she accused Michael of being an angst magnet whos ONLY plots revolve around angst magnet whos ONLY plots revolve around angst.
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  • The Eroica is a true audiophile moving coil cartridge which features an advanced pole shoe design using a powerful rare earth Neodymium magnet.
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  • The Festival's famed Sausage Trail became a magnet for lovers of the British banger.
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  • The chamber is a very powerful magnet, so before entering the room you should remove any metal belongings.
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  • Moving coil, moving magnet The most common types of phono cartridges.
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  • Often the magnet is a superconducting solenoid coil which requires cooling to the temperature of liquid helium.
    0
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  • Just inside the bore of the permanent magnet is a resistive magnet, made from copper conductor in a saddle configuration.
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  • The Scan For your scan you will be positioned on a comfortable couch, which is moved into the magnet.
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  • A strong magnet held on one side of the hand can easily deflect a compass needle on the other side of the same hand.
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  • The magnetic field attracts the thin diaphragm which bends toward the magnet.
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  • As steel cans are attracted to a magnet they can easily be recovered in large volumes from domestic waste using large electromagnets.
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  • Niketown, at Oxford Circus, is a magnet for sports fanatics.
    0
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  • Like iron filings around a magnet, they flew to Daniel.
    0
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  • The PK Ring is a 100% Neo Magnet, with a strong magnetic flux around all external faces.
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  • You will be given the opportunity to design your own unique key fob, fridge magnet, badge or drinks coaster.
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  • Once you have the horseshoe you may obtain iron coins from beneath the grating - for the shoe is in reality a horseshoe magnet.
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  • We pass close by to the working area with a large magnet on a crane jib loading scrap metal into the unit.
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  • But, the material used in the case makes it attract lint and dust like a magnet.
    0
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  • Magnetically shielded All moving coil loudspeakers use some kind of magnet system to produce the movement within the voice-coil.
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  • The selected CD4 cells are washed on a magnet tray and then lysed to release intracellular ATP.
    0
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  • This is a large rotating magnet that hangs above the cans and tins.
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  • Use a slow geared motor to drive it, and attach a strong magnet to the end of the line.
    0
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  • To produce a stable uniform high magnetic field usually requires a superconducting magnet.
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  • The hand-held magnet is placed over the neurostimulator to turn the neurostimulator off or on.
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  • Graham was become dear as her life; he drew her like a powerful magnet.
    0
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  • The Pro PK Kit contains the thinnest and most powerful magnet available-the Micro 5 PK magnet available-the Micro 5 PK magnet.
    0
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  • At the bottom of the lag bolt is a powerful neodymium magnet.
    0
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  • Plus the little fridge magnet thing is way cool.
    0
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  • Plus a water wand containing a 2,300 gauss magnet.
    0
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  • Hence the value of a semiconductor that starts out as a magnet and remains magnetic well above room temperature.
    0
    0
  • A magnet can exert a force on some metals and this force is called magnetism.
    0
    0
  • The Eroica is a true audiophile moving coil cartridge which features an advanced pole shoe design using a powerful rare earth neodymium magnet.
    0
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  • This covers areas from accelerator physics through engineering design, ion optics, radio-frequency engineering, magnet design and a host more.
    0
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  • The display uses a permanent magnet that is perforated to provide an aperture for each pixel.
    0
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  • The sensors contain a permanent magnet and wire coil.
    0
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  • However, there is a commendable moving magnet phono stage that performs better than expected.
    0
    0
  • Furthermore, polarized electrons have been used to make polarized photons in the dilute magnet materials.
    0
    0
  • It was also found that comparatively small magnets were sufficient, and that there was no particular virtue in the closed circuit and electromagnet, but that a small permanent magnet having one pole in contact with FIG.
    0
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  • The Orient was, indeed, ever the magnet which attracted him most; and his hostility to England may be attributed to his perception that she alone stood in the way of his most cherished schemes.
    0
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  • Steel magnets of great strength and of any convenient form may be prepared either in this manner or by treatment with an electromagnet; hence the natural magnet, or lodestone as it is commonly called, is no longer of any interest except as a scientific curiosity.
    0
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  • And again if a piece of steel is weighed in a delicate balance before and after magnetization, no change whatever in its weight can be detected; there is consequently no upward or downward resultant force due to magnetization; the contrary parallel forces acting upon the poles of the magnet are equal, constituting a couple, which may tend to turn the body, but not to propel it.
    0
    0
  • The magnitude of the force is in this case F5 = M/r 3, (16) and its direction is parallel to the axis of the magnet.
    0
    0
  • Just as the lines of flow of an electric current all pass in closed curves through the battery or other generator, so do all the lines of induction pass in closed curves through the magnet or magnetizing coil.
    0
    0
  • The small magnet may be a sphere rigidly magnetized in the direction of Ho; if this is replaced by an isotropic sphere inductively magnetized by the field, then, for a displacement so small that the magnetization of the sphere may be regarded as unchanged, we shall have dW = - vIdHo = v I+-, whence W = - 2 I + H2 ° (37) The mechanical force acting on the sphere in the direction of displacement x is 1 Hopkinson specified the retentiveness by the numerical value of the " residual induction " (=47rI).
    0
    0
  • If A is the moment of inertia of the magnet, and t the time of a complete vibration, MH = 41r 2 A/t 2 (torsion being neglected).
    0
    0
  • The method employed did not admit of the production of such high magnetizing forces, but was of special interest in that both B and I were measured optically-B by means of the rotation of a polarized ray inside a glass plate, as before described, and I by the rotation of a polarized ray reflected from the polished surface of the magnet ized metal (see " Ker.r's constant," Magneto-Optics).
    0
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  • For in his De naturis rerum and De utensilibus (the former of which, at any rate, had become well known at the end of the 12th century, and was probably written about 1180) Neckam has preserved to us the earliest European notices of the magnet as a guide to seamen - outside China, indeed, these seem to be the earliest notices of this mystery of nature that have survived in any country or civilization.
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  • The movements of a ship entirely preclude the employment of any instrument in which a magnet suspended by a fibre has any part, so that the unifilar is unsuited for such observations.
    0
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  • According to both, induction, instead of inferring from A, B, C magnets the conclusion " Therefore all magnets attract iron," infers from the hypothesis, " Let every magnet attract iron," to A, B, C magnets, whose given attraction verifies the hypothesis.
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  • Faraday first succeeded by the simple but ingenious device of using a light magnetic needle tethered flexibly to the bottom of a cup containing mercury so that one pole of the magnet was just above the surface of the mercury.
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  • Accordingly when he sprinkled iron filings on a card held over a magnet and revealed the curvilinear system of lines of force (see Magnetism), he regarded these fragments of iron as simple indicators of a physical state in the space already in existence round the magnet.
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  • Magnet Therapy products can help to readdress this imbalance by allowing the body to repair itself from within.
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  • Under half the UK 's drinks cans are tin-plated steel and stick to a magnet.
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  • However, this is only reported and known magnet related injuries and deaths.
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  • How about a cat Christmas card that comes with its own detachable refrigerator magnet?
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  • Along with this, the turbine is also equipped with a couple of permanent magnet alternators which are connected to the blades.
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  • Falling Water, located southeast of Pittsburgh, was built in 1935 for Pittsburgh department store magnet Edgar Kaufmann.
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  • Iman, which means magnet in Spanish, has created a concept of whole beauty from the inside out.
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  • This shell snaps snugly on to the back of your iPad thanks to its form fitting cut and embedded magnet, giving the device a bit of protection and making it easier to grip.
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  • A Cult of Mac review points out that one of the most appealing features is the fact that the cover has magnet designed to hold the Smart Cover open, describing it as "a rather more useful feature than you might think."
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  • You could also use individual photo flowers to embellish greeting cards or place a rubber magnet on the back of a blossom and use it to decorate your refrigerator.
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  • Couple may also want to add the URL for their wedding website so guests can get more information, and noting that an invitation will follow reassures guests that the magnet itself is not the wedding invitation.
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  • Calendars: Adding a calendar to the magnet - either of the entire wedding year or just the wedding month - makes it a practical reminder for potential guests.
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  • Cards and Envelopes: Most magnet retailers offer cards and envelopes for the magnets to be conveniently mailed.
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  • There are dozens of different magnet manufacturers available who can create beautiful save the date designs.
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  • With a tremendous range of styles available, from fun and quirky designs to sleek, sophisticated magnets, there is a save the date magnet perfect for every couple's special day.
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  • He attended Hamilton Academy of Music in Los Angeles, California, as well as the Magnet School of Performing Arts.
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  • These beds are equipped with 100 mini ceramic biomagnets, and each magnet has a 3,950 gauss rating.
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  • Magnet Therapy Magnets features a variety of magnetic products for your pet, including beds, collars and magnetic therapy sets.
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  • They offer tab books on all of their major albums, including bass tab books for Master of Puppets and Death Magnet.
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  • A magnet without the right strength may come unclasped, causing the wearer to lose the jewelry.
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  • They generally hook onto your frame with a magnet.
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  • If you live in the United States, you can get the Clic style which hang around your neck and then connect via magnet at the bridge.
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  • The Clic Readers are glasses that have a magnet front that opens and closes.
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  • Magnetic resonance imaging (MRI)-An imaging technique that uses a large circular magnet and radio waves to generate signals from atoms in the body.
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  • For parents who desire a local alternative to traditional public and parochial schools, several charter and magnet schools may be available, especially in urban areas.
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  • Magnet schools are public schools that offer specialized programs designed to attract students wishing to enhance particular skills.
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  • Magnet schools were originally formed in the 1960s and 1970s to promote voluntary racial desegregation in urban school districts.
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  • Magnet schools often advertise themselves as "centers of excellence" in a certain area, such as performing arts, science, or mathematics.
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  • Both charter and magnet schools generally have smaller classes and enhanced extracurricular offerings.
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  • The external piece of jewelry is held in place on the outside of the nostril by a small magnet placed inside the nose.
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  • A magnet holds the transmitter in place through its attraction to the receiver-stimulator, a part of the device that is surgically attached beneath the skin in the skull.
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  • Metal objects can be removed from the nose or ears with the help of a magnet.
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  • In rTMS, a large magnet is placed on the patient's head and magnetic fields of different frequency are generated to stimulate the left front cortex of the brain.
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  • Origami frogs can be pinned to bulletin boards, placed on the refrigerator with a magnet glued to its underside, or can adorn a gift box.
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  • Like a magnet, San Francisco has long pulled people to its up-and-down hills, spectacular scenes, and its unique and unrestrained cosmopolitan character.
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  • The filter uses an electronically charged metal grid that captures particles much like a magnet.
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  • Finally, a small memento such as a refrigerator magnet or a religious bookmark can be included as either a thank you or a reminder.
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  • A fridge magnet with an image of the couple is likely to raise a smile for many years to come.
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  • Features for the Giselle include the typical interior cell phone pocket as well as one interior zip pocket and an external magnet snap closure.
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  • These numbers are the vibration of your essence and act like a magnet.
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  • Magnet Schools - These schools focus on a specific interest area or a specific population of students.
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  • There are magnet programs for the arts, for science, for math, and for other subject areas.
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  • For example, Los Angeles Unified School District has a zoo magnet program.
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  • There may also be magnet programs for gifted and talented students.
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  • Normally, parents complete applications for a magnet program, and then students are selected by program criteria or by lottery.
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  • Other schools may focus on a specific area of curriculum, similar to magnet schools within a public school district.
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  • Ironically, children seem to have an innate magnet for sharing precisely when they are not supposed to.
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  • With so many natural, cultural and historical attractions, the world's largest, most populous country has become a tourist magnet, and there are several travel agencies specializing in getting you great China travel deals.
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  • Charleston beaches are a tourist magnet in the spring as well.
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  • If your penny sticks to a magnet, you know that you have one of the zinc-coated variety and is not all that rare.
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  • However, if your 1943 copper penny is not attracted to a magnet, it may be a rare coin worth tens of thousands.
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  • Apples 4 the Teacher: Check out this religious fall squirrel magnet.
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  • Use the photo as the centerpiece of your card, with a note that tells the recipient to enjoy the magnet long after the holiday season has passed.
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  • Magnet sheets turn ordinary paper into a fun craft for Easter.
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  • Peel the protective backing off of a magnet sheet and carefully align the card stock on top.
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  • At a farewell party, give guests a magnet with the honoree's new address printed on the front.
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  • Taylor attends a magnet public school in Tribeca where she is an active member of her school's gymnastics and roller hockey teams.
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  • Owens has been a magnet for media criticism as well as the criticism of his fellow players.
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  • The warmth of his muscular chest was like a magnet.
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  • Katie looked to the fridge, where a small business card was stuck beneath a cartoon magnet.
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  • Striding back to the kitchen, he deliberately removed the caduceus magnet and centered the picture on the refrigerator door – eye level.
    28
    28
  • Smiling, he anchored it with the magnet.
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    1
  • In the second, or " braking off " method, the brake is automatically applied by a spring or weight, and is released either mechanically or, in the case of electric cranes, by the pull of a solenoid or magnet which is energized by the current passing through the motor.
    7
    7
  • A small permanent magnet is always liable to become demagnetized, or have its polarity reversed by the action of lightning.
    8
    9
  • This liability is overcome by making such movable parts as require to be magnetic of soft iron, and magnetizing them by the inducing action of a strong permanent magnet.
    0
    1
  • These tongues are magnetized by the inducing action of a strong horse-shoe permanent magnet, S N, which is made in a curved shape for the sake of compactness.
    13
    13
  • The electromagnet consists of two coils, each wound on a soft iron core fixed to the poles of a strong permanent horse-shoe magnet.
    0
    1
  • The armature of the electromagnet is normally attracted by the effect of the permanent magnet, but it is furnished with two antagonistic springs tending to throw it upwards.
    4
    4
  • The shafts are turned by the pull of the magnet upon the coils, and the motions of the transmitting pencil are thus reproduced.
    7
    7
  • The recorder coil is connected mechanically to a second similar coil, which is suspended between the poles of a laminated magnet, so that the motions of the two are similar.
    4
    4
  • This magnet is excited by an alternating current, and the current induced in the second coil is after rectification sent through an ordinary siphon recorder.
    3
    4
  • The capillary tube can be raised or lowered at will by running a magnet outside the tube, and the heights of the columns are measured by a cathetometer or micrometer microscope.
    7
    7
  • In Englishspeaking countries the ore is commonly known as magnetite, and pieces which exhibit attraction as magnets; the cause to which the attractive property is attributed is called magnetism, a name also applied to the important branch of science which has been evolved from the study of phenomena associated with the magnet.
    0
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  • The regions of greatest attraction have received the name of poles, and the line joining them is called the axis of the magnet; the space around a magnet in which magnetic effects are exhibited is called the field of magnetic force, or the magnetic field.
    3
    4
  • The other phenomenon is mentioned by Greek and Roman writers of the 1st century: a piece of iron, when brought into contact with a magnet, or even held near one, itself becomes " inductively " magnetized, and acquires the power of lifting iron.
    12
    12
  • If the iron is soft and fairly pure, it loses its attractive property when removed from the neighbourhood of the magnet; if it is hard, some of the induced magnetism is permanently retained, and the piece becomes an artificial magnet.
    4
    5
  • Magnetism may be imparted to a bar of hardened steel by stroking it several times from end to end, always in the same direction, with one of the poles of a magnet.
    0
    1
  • Steel articles, such as knitting or sewing needles and pieces of flat spring, may be readily magnetized by stroking them with the bar-magnet; after having produced magnetism in any number of other bodies, the magnet will have lost nothing of its own virtue.
    9
    9
  • The compass needle is a little steel magnet balanced upon a pivot; one end of the needle, which always bears a distinguishing mark, points approximately, but not in general exactly, to the north,' the vertical plane through the direction of the needle being termed the magnetic meridian.
    3
    4
  • The wire will in fact become temporarily magnetized by induction, that end of it which is nearest to the pole of the magnet acquiring opposite polarity, and behaving as if it were the pole of a permanent magnet.
    6
    6
  • Even a permanent magnet is susceptible of induction, its polarity becoming thereby strengthened, weakened, or possibly reversed.
    7
    7
  • If one pole of a strong magnet is presented to the like pole of a weaker one, there will be repulsion so long as the two are separated by a certain minimum distance.
    3
    4
  • At shorter distances the magnetism induced in the weaker magnet will be stronger than its permanent magnetism, and there will be attraction; two magnets with their like poles in actual contact will always cling together unless the like poles are of exactly equal strength.
    4
    4
  • Induction is an effect of the field of force associated with a magnet.
    0
    1
  • Magnetic force has not merely the property of acting upon magnetic poles, it has the additional property of producing a phenomenon known as magnetic induction, or magnetic flux, a physical condition which is of the nature of a flow continuously circulating through the magnet and the space outside it.
    6
    6
  • Inside the magnet the course of the flow is from the south pole to the north pole; thence it diverges through the surrounding space, and again converging, re-enters the magnet at the south pole.
    7
    7
  • When the magnetic induction flows through a piece of iron or other magnetizable substance placed near the magnet, a south pole is developed where the flux enters and a north pole where it leaves the substance.
    7
    7
  • A map indicating the direction of the force in different parts of the field due to a magnet may be constructed in a very simple manner.
    4
    4
  • A line of force is regarded as proceeding from the north pole towards the south pole of the magnet, its direction being that in which an isolated north pole would be urged along FIG.
    6
    6
  • When the compass is far from the magnet, the vibrations will be comparatively slow; when it is near a pole, they will be exceedingly rapid, the frequency of the vibrations varying as the square root of the magnetic force at the spot.
    7
    7
  • It is to the non-uniformity of the field surrounding a magnet that the apparent attraction between a magnet and a magnetizable body such as iron is ultimately due.
    18
    18
  • Gilbert in 1600, that the earth itself is a great magnet, having its poles at the two places where the dipping needle is vertical.
    16
    17
  • But no magnet can have a single pole; if there is one, there must also be at least a second, of the opposite sign and of exactly equal strength.
    7
    7
  • The process of magnetization consists in turning round the molecules by the application of magnetic force, so that their north poles may all point more or less approximately in the direction of the force; thus the body as a whole becomes a magnet which is merely the resultant of an immense number of molecular magnets.
    0
    1
  • In every magnet the strength of the south pole is exactly equal to that of the north pole, the action of the same magnetic force upon the two poles being equal and oppositely directed.
    0
    1
  • The poles at the ends of an infinitely thin uniform magnet, or magnetic filament, would act as definite centres of force.
    0
    1
  • An actual magnet may generally be regarded as a bundle of magnetic filaments, and those portions of the surface of the magnet where the filaments terminate, and socalled " free magnetism " appears, may be conveniently called poles or polar regions.
    0
    1
  • A more precise definition is the following: When the magnet is placed in a uniform field, the parallel forces acting on the positive poles of the constituent filaments, whether the filaments ' For the relations between magnetism and light see Magnetooptics.
    0
    1
  • The point N, which is the centre of the parallel forces, is called the north or positive pole of the magnet.
    0
    1
  • The opposite and parallel forces acting on the poles are always equal, a fact which is sometimes expressed by the statement that the total magnetism of a magnet is zero.
    0
    1
  • The line joining the two poles is called the axis of the magnet.
    0
    1
  • A magnetic field is generally due either to a conductor carrying an electric current or to the poles of a magnet.
    0
    1
  • The moment, M, M or V, of a uniformly and longitudinally magnetized bar-magnet is the product of its length into the strength of one of its poles; it is the moment of the couple acting on the magnet when placed in a field of unit intensity with its axis perpendicular to the direction of the field.
    0
    1
  • If 1 is the length of the magnet, M = ml.
    1
    1
  • The action of a magnet at a distance which is great compared with the length of the magnet depends solely upon its moment; so also does the action which the magnet experiences when placed in a uniform field.
    0
    1
  • The moment of a small magnet may be resolved like a force.
    0
    1
  • If the magnet is not uni - form, the magnetization at any point is the ratio of the moment of an element of volume at that point to the volume itself, or I = m.ds/dv.
    0
    1
  • If the direction of the magnetization at the surface of a magnet makes 3 The C.G.S.
    0
    1
  • The potential due to a thin magnet at a point whose distance from the two poles respectively is r and r' is V =m(l/r=l/r') (8) When V is constant, this equation represents an equipotential surface.
    0
    1
  • The potential due to a small magnet of moment M, at a point whose distance from the centre of the magnet is r, is V=M cos 0/r 2, (io) where 0 is the angle between r and the axis of the magnet.
    0
    1
  • For a point in the line OY bisecting the magnet perpendicularly, 0 =42 therefore cos 0 =0, and the point D is at an infinite distance.
    0
    1
  • Although the above useful formulae, (io) to (15), are true only for an infinitely small magnet, they may be practically applied whenever the distance r is considerable compared with the length of the magnet.
    0
    1
  • If a small magnet of moment M is placed in the sensibly uniform field H due to a distant magnet, the couple tending to turn the small magnet upon an axis at right angles to the magnet and to the force is MH sin 0, (17) where 0 is the angle between the axis of the magnet and the direction of the force.
    0
    1
  • A magnet may be regarded as consisting of an infinite number of elementary magnets, each having a pair of poles and a definite magnetic moment.
    1
    1
  • A magnet which consists entirely of such solenoids, having their ends either upon the surface or closed upon themselves, is called a solenoidal magnet, and the magnetism is said to be distributed solenoidally; there is no free magnetism in its interior.
    0
    1
  • If the constituent solenoids are parallel and of equal strength, the magnet is also uniformly magnetized.
    1
    1
  • A magnet which can be divided into simple magnetic shells, either closed or having their edges on the surface of the magnet, is called a lamellar magnet, and the magnetism is said to be distributed lamellarly.
    0
    1
  • A magnet consisting of a series of plane shells of equal strength arranged at right angles to the direction of magnetization will be uniformly magnetized.
    0
    1
  • Since 7ra'I is the moment of the sphere (=volume X magnetization), it appears from (10) that the magnetized sphere produces the same external effect as a very small magnet of equal moment placed at its centre and magnetized in the same direction; the resultant force therefore is the same as in (14).
    0
    1
  • When it is desired to have a uniform magnet with definitely situated poles, it it usual to employ one having the form of an ovoid, or elongated ellipsoid of revolution, instead of a rectangular or cylindrical bar.
    0
    1
  • If the magnetization is parallel to the major axis, and the lengths of the major and minor axes are 2a and 2C, the poles are situated at a distance equal to 3a from the centre, and the magnet will behave externally like a simple solenoid of length 3a.
    0
    1
  • Kohlrausch 2 the distance between the poles of a cylindrical magnet the length of which is from io to 30 times the diameter, is sensibly equal to five-sixths of the length of the bar.
    0
    1
  • In the case of a straight uniformly magnetized bar the direction of the magnetic force due to the poles of the magnet is from the north to the south pole outside the magnet, and from the south to the north inside.
    0
    1
  • In certain cases, as, for instance, in an iron ring wrapped uniformly round with a coil of wire through which a current is passing, the induction is entirely within the metal; there are, consequently, no free poles, and the ring, though magnetized, constitutes a poleless magnet.
    0
    1
  • Forces acting on a Small Body in the Magnetic Field.-If a small magnet of length ds and pole-strength m is brought into a magnetic field such that the values of the magnetic potential at the negative and positive poles respectively are V 1 and the work done upon the magnet, and therefore its potential energy, will be W =m(V2-Vi) =mdV, which may be written W =m d s- = M d v= - MHo = - vIHo, ds ds where M is the moment of the magnet, v the volume, I the magnetization, and Ho the magnetic force along ds.
    0
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  • The small magnet may be a sphere rigidly magnetized in the direction of Ho; if this is replaced by an isotropic sphere inductively magnetized by the field, then, for a displacement so small that the magnetization of the sphere may be regarded as unchanged, we shall have dW = - vIdHo = v I+-, whence W = - 2 I + H2 ° (37) The mechanical force acting on the sphere in the direction of displacement x is 1 Hopkinson specified the retentiveness by the numerical value of the " residual induction " (=47rI).
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  • The product MH is first determined by suspending the magnet horizontally, and causing it to vibrate in small arcs.
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  • M/H = (d 2 -1 2) tan 0/2d, where 1 is half the length of the magnet, which is placed in the " broadside-on " position as regards a small suspended magnetic needle, d the distance between the centre of the magnet and the needle, and 0 the angle through which the needle is deflected by the magnet.
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  • Thus if the magnet is suspended horizontally by a fine wire, which, when the magnetic axis points north and south, is free from torsion, and if 0 is the angle through which the upper end of the wire must be twisted to make the magnet point east and west, then MH = CB, or M = C6/H, where C is the torsional couple for r 0.
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  • If P is the weight of the magnet, l the length of each of the two threads, 2a the distance between their upper points of attachment, and 2b that between the lower points, then, approximately, MH = P(ab/l) sin 0.
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  • The sample to be inserted between the magnet poles was prepared in the form of a bobbin resembling an ordinary cotton reel, with a short narrow neck (constituting the " isthmus ") and conical ends.
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  • It is shown in the paper that the greatest possible force which the isthmus method can apply at a point in the axis of the bobbin is F = 11, 137 I, log i n b/a, I, being the saturation value of the magnet pores, a the radius of the neck on which the cones converge, and b the radius of the bases of the cones.
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  • The field magnet of the dynamo has two gaps in it.
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  • The thin disk of mercury is therefore traversed perpendicularly by lines of magnetic force when the magnet is excited.
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  • In this instrument there is a fixed permanent magnet, producing a.
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  • Johnson, R.N., showed from experiments in the iron steamship "Garry Owen" that the vessel acted on an external compass as a magnet.
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  • The heart of a normal eddy current separator is a powerful permanent magnet that revolves at very high speed.
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  • The wheel magnet attaches to conventional three crossed spoke pattern wheels, bladed or radial spokes may require an alternate spoke magnet.
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  • It was a prime terror target, a magnet for anarchists, warned the press.
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  • Smaller tools will include a hand lens, hardness tester, color char and magnet.
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  • Another series of experiments with the magnet variometers was conducted in New Hampshire between November 1970 and September 1972.
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  • The armature is placed between the poles of the electromagnet, and being magnetized by the magnet m it will oscillate to the right or left under the action of the poles of the electromagnet M according as the current passes through M in one direction or the other.
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  • A magnet is small and simple, yet because it can be affixed to any metallic surface - a filing cabinet, refrigerator, metal shelves, etc. - it is less likely to be lost or forgotten as the wedding date approaches.
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  • The magnet between the poles of which the rectangular signal coil moves is built up of a number of thin flat horseshoe-shaped permanent magnets of a special quality of steel, and is provided with adjustable pole pieces.
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  • It is essential that the permanent magnet should be subjected to a process of ageing so that its field may not be liable to change subsequently with time.
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  • Upon one of these is based the principle of the mariner's compass, which is said to have been known to the Chinese as early as I ioo B.C., though it was not introduced into Europe until more than 2000 years later; a magnet supported so that its axis is free to turn in a horizontal plane will come to rest with its poles pointing approximately north and south.
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  • The north-seeking end of a magnet is in English-speaking countries called the north pole and the other end the south pole; in France the names are interchanged.
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