There is a magnetic friction force in a dynamo?

[DanteBR]

There is a "magnetic friction force" in a dynamo?

In a rotating dynamo, where the magnet rotates surrounded by a coil, there is something like a "magnetic friction force"? The magnetic field causes an effect similar to mechanical friction, that can slow down the revolving magnet?

 

[DanteBR]

Does anyone know if such a thing exist?

Imagine that the dynamo is in a vacuum chamber. The rotating magnet does not touch the coil, and there is no air, so there is no aerodynamic drag.

So, I wonder if there is something like a "magnetic friction force", decelerating the rotating magnet. There is this?

 

[bp_psy]

http://hyperphysics.phy-astr.gsu.edu/HBASE/electric/farlaw.html

 

[Redbelly98]

So, I wonder if there is something like a "magnetic friction force", decelerating the rotating magnet. There is this?

Yes, it is well known. Some power tools employ the effect to stop motors quickly. It's a safety feature in for example power saws and electric lawnmowers.

 

[sardar]

Yes, there is a phenomenon known as magnetic hysteresis which can be considered as a form of magnetic friction in a dynamo. This occurs when the magnetic field in the rotating magnet interacts with the surrounding materials, causing a resistance to the rotation. This can result in a decrease in efficiency and a slowing down of the rotation of the magnet. However, this effect can be minimized through careful design and selection of materials to reduce the hysteresis losses. Overall, while magnetic friction does exist in a dynamo, it can be managed and optimized to ensure efficient operation.