The magnetic flux density along symmetric axis of the quadric surface of revolution
Ding Zhang · College Physics · 2006
Basing on a problem in The Feynman Lectures(Vol.2),it is proved that the magnetic flux density along the axis of the ellipsoid of revolution which has coil on its surface is a constant under the condition which Feynman pro-vided.Then it turned out that this case is suitable for all the quadric surfaces of revolution.At last a general formula is obtained applicable to them all.