Problem: Calculating the eddy current distribution inside an infinitely long cylindrical conductor inside a straight and infinitely long solenoid energized by an alternating sinusoidal current. The problem has a perfect summery and we know that magnetic field and the eddy current depend on radial dimension only ( and of course on time). The problem looks simple and I'm sure this problem has been solved perhaps in 19th century, but I can't find the solution in the net. In fact when I attempted to solve it by myself, It was required to solve Bessel's differential equation and i made doubt about my approach. Is the problem this much complicated really? Your helps and comments is appreciated.