How does eddy current affect two magnets spinning at 2000 RPM?

[gareth01422]

Hi guys

I may have posted in the wrong section.

If I have 2 magnets pushing away from each other (one is fixed) the other is on a crank. And the crank is spinning around 2000 RPM (33.33 crank rotations every second) how will eddy current effect the 2 magnets?

I have Wikied "eddy current" and read the page but still don't understand how this would effect my mind experiment.

Can someone explain it to me in simple terms?

Gareth

 

[Per Oni]

If I have 2 magnets pushing away from each other (one is fixed) the other is on a crank. And the crank is spinning around 2000 RPM (33.33 crank rotations every second) how will eddy current effect the 2 magnets?
Gareth

Do you mean the eddy currents running in the magnetic materials? If so then I don’t think they will be big because the electrical resistivity is quite high for those.
Having said that you’ve got quite a speed. To work out the voltage each time the magnet cycles you could perhaps wind a search coil with say 10 windings or more and look on an ac meter what the generated voltage is. (divide again by 10 or more).
Then you have to estimate the resistance of where ever the currents are running. If they are running in a copper plate then they will be high. As usual I=U/R. This will give you a rough idea.

 

[astrokreng]

Hello Gareth,

Eddy currents are circular electric currents that are induced in a conductor when it is exposed to a changing magnetic field. In the case of your mind experiment, the spinning magnet on the crank is creating a changing magnetic field around it as it rotates at 2000 RPM. This changing magnetic field will induce eddy currents in the fixed magnet, causing it to also experience a force that pushes it away from the spinning magnet.

The strength and direction of the eddy current will depend on the material and shape of the fixed magnet, as well as the speed and direction of the spinning magnet. The faster the spinning magnet, the stronger the eddy currents will be and the greater the force pushing the fixed magnet away. This can also be affected by the distance between the two magnets and any other external factors that may influence the magnetic field.

In simple terms, the eddy currents created by the spinning magnet will cause the fixed magnet to experience a force that pushes it away. This is due to the interaction between the changing magnetic field and the fixed magnet's conductive material. I hope this helps to clarify the concept of eddy currents and how they can affect two magnets spinning at 2000 RPM.