Inductive sensor

The inductive sensor is based on Faraday's law of induction. The temporal variations of the Magnetic Flux ${\displaystyle \Phi }$ through a N turns circuit will induce a voltage ${\displaystyle e}$ which follows:

which can be expressed in a simpler way:

by assuming that the induced magnetic field B is homogeneous over a section S (the Magnetic flux will be expressed ${\displaystyle \Phi =B\times S}$).

Inductive sensors constitute the main element to build a search coil magnetometer also known as search coil. These are used in many fields of research: magnetotellurics electromagnetic waves measurement, space magnetometers to investigate electromagnetic waves in space plasma as well as natural electromagnetic waves observations on Earth.

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