CollectiveRocker
Dec7-04, 01:52 PM
I began out with a small solid conductor of radius a is supported by insulating nonmagnetic disks on the axis of a thin-walled tube with inner radius b. The inner and outer conductors carry equal currents i in opposite directions. Now I know from part a) that B = (µi)/ (2πr). Now the place which I think is iffy about this whole thing is part b), which says to write the expression for the flux through a narrow strip of length l parallel to the axis, of width dr, at a distance r from the axis of the cable and lying in a plane containing the axis. I realized that magnetic flux = BA cos θ, and ended up with (µil)/ (2π) integral (dr/r). Can someone please check my math? I really would appreciate it.