Sunday, July 15, 2018

Candle flame is repelled by magnets (and Zeeman follow-up)

Why is a candle flame repelled by magnets? It turns out to be a combination of diamagnetic soot particles and hot gas.

Dr. Faraday on the diamagnetic condition:

On Flame and Gases:

I should have mentioned in the video that the exhaust from a flame will be oxygen-poor, thus also making it more diamagnetic than normal air.  Air is a mixture of nitrogen (diamagnetic) and oxygen (paramagnetic). Removing the oxygen will make the resulting gas more diamagnetic.

1 comment:

  1. Also the gas is in motion (hotter air moves away from acceleration of gravity), so any charges that exist on the particles are going to make them steer out away from the strong field. That would also explain why the bubble didn't seem to be affected. Maybe you could test that by blowing a stream of /cold/ air between the magnets at different speeds.