Search results
Results from the WOW.Com Content Network
By Lenz's law, an eddy current creates a magnetic field that opposes the change in the magnetic field that created it, and thus eddy currents react back on the source of the magnetic field. For example, a nearby conductive surface will exert a drag force on a moving magnet that opposes its motion, due to eddy currents induced in the surface by ...
When a magnetic field moves through a conductor the movement induces an eddy current in the conductor. The flow of electrons in the conductor immediately creates an opposing magnetic field which results in damping of the magnet and produces heat inside the conductor similar to heat buildup inside of a power cord during use.
[1] [2] Damping is an influence within or upon an oscillatory system that has the effect of reducing or preventing its oscillation. [3] Examples of damping include viscous damping in a fluid (see viscous drag), surface friction, radiation, [1] resistance in electronic oscillators, and absorption and scattering of light in optical oscillators.
The Induced current is the current generated in a wire due to change in magnetic flux. An example of the induced current is the current produced in the generator which involves rapidly rotating a coil of wire in a magnetic field. It is a qualitative law that specifies the direction of induced current, but states nothing about its magnitude.
Electrodynamic suspension (EDS) is a form of magnetic levitation in which there are conductors which are exposed to time-varying magnetic fields. This induces eddy currents in the conductors that creates a repulsive magnetic field which holds the two objects apart. These time-varying magnetic fields can be caused by relative motion between two ...
The damping of the dynamical magnetisation is accounted for phenomenologically by the Gilbert damping constant in the Landau-Lifshitz-Gilbert equation (LLG equation), the energy loss mechanism itself is not completely understood, but is known to arise microscopically from magnon-magnon scattering, magnon-phonon scattering and losses due to eddy ...
The wave modes derived using the MHD equations are called magnetohydrodynamic waves or MHD waves. There are three MHD wave modes that can be derived from the linearized ideal-MHD equations for a fluid with a uniform and constant magnetic field: Alfvén waves; Slow magnetosonic waves; Fast magnetosonic waves
In metals the damping forces described by the constant λ are in many cases dominated by the eddy currents. One important difference between phonons and magnons lies in their dispersion relations. The dispersion relation for phonons is to first order linear in wavevector k, namely ώ = ck, where ω is frequency, and c is the velocity of sound.