I am a chemical engineer, not a physicist, so I am a bit rusty on my electromagnetics. I need to set up a fluctuating magnetic field inside of a stainless steel tube (hopefully using a pair of electromagnets outside the tube), and I am wondering if the field will penentrate through the tube. I imagine that within some frequency range of oscillation the tube will act as an antenna, but assuming I am below that frequency, will it work? The tube has 10mm ID and 1mm wall thickness and contains water. Thanks in advance for any input.