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which can measure one or more components of the magnetic field. A classical configuration uses three orthogonal inductive sensors. The search-coil magnetometer can measure magnetic field from mHz up to hundreds of MHz.
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of the ferromagnetic core response to an external magnetic field. The magnetization is reduced by the demagnetizing field.
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core, that increases the sensitivity of the sensor thanks to the apparent permeability of the ferromagnetic core.
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The demagnetizing coefficient can easily be computed in the case of simple shapes (spheres and ellipsoids).
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Figure 1: Induction sensor made up of a winding (orange) surrounding a ferromagnetic core (grey)
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733:{\displaystyle -Ne=NS\mu _{app}{\frac {N\mathrm {d} B}{\mathrm {d} t}}}
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584:{\displaystyle \mu _{app}={\frac {\mu _{r}}{1+N_{z}(\mu _{r}-1)}}}
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273:{\displaystyle e=-N{\frac {\mathrm {d} \Phi }{\mathrm {d} t}}}
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The magnetic amplification, known as apparent permeability
335:{\displaystyle e=-NS{\frac {\mathrm {d} B}{\mathrm {d} t}}}
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Natural electromagnetic waves observations on Earth.
60:. Unsourced material may be challenged and removed.
759:using coils that are embedded into a contact lens.
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156:. An inductive sensor connected to a conditioning
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120:Learn how and when to remove this message
652:is the demagnetizing coefficient in the
283:which can be expressed in a simpler way
445:Search coil using a ferromagnetic core
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659:The induced voltage will be written
204:turns circuit will induce a voltage
58:adding citations to reliable sources
755:: a search coil is used to measure
792:Magnetic Sensors and Magnetometers
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800:Induction Coil Sensors - a Review
422:) may be increased several ways:
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177:. The temporal variation of the
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382:{\displaystyle \Phi =B\times S}
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449:When a coil is wound around a
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819:(Uses a magnetic search coil)
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487:{\displaystyle \mu _{app}}
433:increase the turn number (
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148:and inductive coil), is a
69:"Search coil magnetometer"
794:, Artech House Publishers
440:use a ferromagnetic core.
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134:search coil magnetometer
18:Search-coil magnetometer
766:Non-destructive testing
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645:{\displaystyle N_{z}}
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54:improve this article
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16:(Redirected from
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771:Magnetotellurics
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27:Measuring tool
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71: –
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65:Find sources:
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43:This article
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817:Waves (Juno)
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747:Applications
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52:Please help
47:verification
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753:Eye tracker
656:direction.
827:Categories
785:References
200:through a
80:newspapers
762:Education
689:μ
670:−
603:μ
570:−
561:μ
531:μ
510:μ
470:μ
374:×
365:Φ
300:−
255:Φ
241:−
188:Φ
169:Principle
110:June 2016
811:See also
621:is the
94:scholar
833:Vision
594:where
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353:(the
101:JSTOR
87:books
132:The
73:news
389:).
136:or
56:by
829::
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430:),
725:t
721:d
715:B
711:d
707:N
699:p
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682:N
679:=
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607:r
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557:(
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525:=
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435:N
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371:B
368:=
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303:N
297:=
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238:=
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202:N
123:)
117:(
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108:(
98:·
91:·
84:·
77:·
50:.
20:)
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