Hey all, I'm just working through the london theory of superconductors. I've dervied the london penetration depth, the distance for the amplitude to drop by a factor of 1/e... Seems simple... Now my book talks about applying a an ac magnetic field to a superconductor. How would the field in the superconductor change as a function of time? I think it should just effectively be a waveform of the same form frequency of the ac magnetic field applied to it with a smaller amplitude? Any discussion would be greater! Struggling to see any different from this!