According to Faraday’s Law of Electromagnetic Induction, an inductor is a material that develops a magnetic field in response to a flowing current and conversely, in which a current is generated if the magnetic field changes. This relationship is widely used to detect the proximity or movement of conducting (metal) objects. In fact, innovative arrangements of inductive sensors allow them to be used to sense vibration, strain, pressure, displacement, flow and several other parameters. A more advanced application is for exploring electromagnetic waves in magnetotellurics and astrophysics.
