I am a physicist, a young physicist. I can't find information that agrees on how to determine the magnetic field at a distance from a solenoid. We use a ferrite rod of 7.5" long wound with wire over 6.5" of it. The frequency it oscillates at is 73 kHz. If I know the current how can I determine the magnetic field at any point in space. I have looked everywhere and I get different information everywhere. I need some help.