Can Magnetic Fields Induce Currents and Heat in Metal?

[brainyman89]

let's say we have a square piece of metal and we put this piece in a variable magnetic field, would it get heated? is this the idea of a current?

If we have a rotating metal disk (as the case of a saw for instance), and then we put this rotating disk in a constant uniform magnetic field such that angle between normal vector and B vector is 0 and is not changing since the disk is rotating along the normal axis, would this disk stop rotating? if yes how comes eddy currents are induced though we are not changing any of these area, B nor the angle? if no then what is the idea of creating brakes by eddy currents?

if we have a short piece of straight rectilinear wire in motion with velocity V in a uniform constant magnetic field, would we have a potential difference(voltage) on the edges of this wire? if yes how comes we got induced emf without changing any of these area, B nor the angle?

thanks in advance

 

[brainyman89]

anybody?

 

[brainyman89]

then what is the idea of eddy current

 

[willum97]

if we have a short piece of straight rectilinear wire in motion with velocity V in a uniform constant magnetic field, would we have a potential difference(voltage) on the edges of this wire? if yes how comes we got induced emf without changing any of these area, B nor the angle?

thanks in advance

If you place 2 sliders in touch with the opposite edges of the wire, and say the sliders are stationary relative to the magnetic field, then a voltage is generated between the sliders. If there are no sliders and the B field is not uniform over the length of this wire, then there will be Eddy currents.

Your question is similar to the Hall effect, although in that case only the electrons are moving in a stationary magnetic field and there are no sliders but electrodes stationary with a wire and B field.