I have a question about magnetic bars. If we froze a magnetic bar down to zero Kelvin, does it still have a magnetic field?
Maybe you should consider this. How would one destroy the magnetic strength of a permanent magnet? Does one chill down to low temperatures, or does one heat it up? If you can answer this question (which, I think, is something that is covered in elementary science classes), then you have a clue in the answer to your question.OK, we can not reach absolute zero, but we can reach as low as several K. So what does the magnetic field change when the m-bar is freezed to that low temperature? Will it increase or decrease?